Exhibition matches

As of in his 2017 season, Nadal's schedule before the Australian Open included the World Tennis Championship, in Abu Dhabi, the Brisbane International and the Fast4 Showdown, in Sydney. However, he pulled out of all three events due to a knee injury.^[1][2] His season started in Melbourne with a match against Richard Gasquet, included in the Kooyong Classic exhibition tournament, which he lost in straight sets.^[3] On the day after, Nadal moved on to play the Tie Break Tens, another exhibition tournament where only tie-break matches are played.^[4] He defeated Lucas Pouille in the quarterfinals and Lleyton Hewitt in the semifinals, before losing in the final against Tomáš Berdych. Nadal closed his Australian Open preparation with another exhibition match against Dominic Thiem in the Margaret Court Arena, which he won in a third-set match tiebreaker.^[5]

Australian Open

In the first major tournament of the year, the Australian Open, Nadal was the top seed, knowing that he would need to reach the quarterfinals in order to secure the No. 1 position in the ATP rankings. Despite playing his first official match in more than two months, Nadal easily defeated Víctor Estrella Burgos in straight sets. Following strong performances in straight sets victories against Leonardo Mayer and Damir Džumhur, he defeated Diego Schwartzman in the fourth round, reaching the quarterfinals and thus retaining the world No. 1 status. In the quarterfinals he faced World No. 6 Marin Čilić, and despite leading two sets to one, he eventually had to retire after going down a break in the fifth set due to a hip injury.^[6]

Mexican Open

Having been relegated to No. 2 in the ATP rankings a week before, Nadal was set to play at the Mexican Open. However, he was forced to again pull out of the tournament due to the hip injury sustained at the Australian Open that was aggravated in a practice session.^[7] On 2 March 2018, through his Facebook account, Nadal announced the withdrawal from the season's first two Masters 1000 tournaments: the Indian Wells Masters and the Miami Open.^[8] Despite his absence, Nadal regained the world No. 1 position on 2 April 2018, due to Roger Federer losing in the second round of the Miami Open.

Davis Cup World Group quarterfinals

As announced on 27 March 2018 by the Spain Davis Cup team captain Sergi Bruguera, Nadal represented his country participating in the Davis Cup World Group quarterfinal tie against Germany, in Valencia.^[9] These were Nadal's first matches since his Australian Open defeat, more than two months later. Nadal won both his singles rubbers, against Philipp Kohlschreiber and Alexander Zverev, in straight sets, to help Spain advancing to the semifinals.

Monte-Carlo Masters

At the Monte-Carlo Masters, Nadal successfully defended his title by winning an unprecedented 11th title in Monte-Carlo, reaching the finals without dropping a set and not losing more than 4 games in each set that he played against Aljaž Bedene, Karen Khachanov, Dominic Thiem and Grigor Dimitrov. In the final, he halted former top 4 player Kei Nishikori's resurgence by beating him in straight sets, extending his clay winning streak to 36 sets in a row. Additionally, none of his opponents were able to win more than 4 games in each of those 36 sets. This tournament victory marked the Spaniard's 31st Masters 1000 title, putting him yet again at the top of most Masters 1000 titles won, passing rival Novak Djokovic who stands at 30. His 36 straight sets won on clay also became a record, surpassing both Ilie Nastase and Guillermo Coria, who won 34 and 35 straight sets respectively and are the only players to win 30 or more consecutive sets on clay other than Nadal. In that process, he also retained his World No. 1 ranking for another week.

Barcelona Open

Coming to Barcelona, Nadal again required to defend his title at the Barcelona Open if he were to retain his no.1 ranking, which he did in pure dominance. He extended his record of straight sets won on clay to 46 consecutive sets, with Martin Klizan, Nadal's quarterfinal opponent becoming the first man to take more than 4 games off in a single set against Nadal since Dominic Thiem beat him at last year's Rome Masters. Nadal's semifinal win against David Goffin was his 400th match won on clay, making him the only player, of either gender, to win at least 400 matches in both clay and hard courts. In the final, he defeated Greek rising star Stefanos Tsitsipas in straight sets with the loss of only 3 games, despite the Greek having not lost a single set in the tournament. This victory was his 11th Barcelona Open title and his 77th overall. The win marked his 20th ATP 500 series title, which put him back atop the list of most ATP 500 titles, tied with Roger Federer. Additionally, it marked his 14th consecutive season in which he won at least 1 ATP 500 title.

Madrid Open

Fresh after achieving the 'Undecima' of Monte Carlo and Barcelona titles, Nadal had to defend yet another title at Madrid if he were to retain his No. 1 ranking, with the tournament taking place on his home soil. He reached the quarterfinals, defeating Gael Monfils and Diego Schwartzman in straight sets, to extend his record to 50 consecutive sets on clay starting from 2017 French Open. His win over Schwartzman broke John McEnroe's record of 49 straight sets won on a single surface.^[10] McEnroe had previously achieved the record on carpet in 1984. In a surprise, Nadal lost in straight sets to Dominic Thiem in quarterfinals, ending his 21-match and record 50-set winning streak on clay. He also relinquished his world no. 1 ranking to Federer in the process.

Italian Open

Nadal next participated at the Italian Open with a chance to regain his No.1 ranking if he were to win the tournament, which he did convincingly. He started off fresh and dominant, dispatching both Damir Džumhur and Canadian #NextGen Denis Shapovalov in just the loss of 6 games. He reached the semifinals by mounting a comeback against home-favourite Fabio Fognini after losing the first set. In the semifinals, he faced his resurging arch-rival Novak Djokovic for the 51st time, beating him in two sets after a tight first set tiebreak. This victory was his 356th match win in Masters 1000 level, thus surpassing Roger Federer for most matches won in the category. He faced in form German Alexander Zverev in the finals who was riding on a 13-match winning streak after reaching his 3rd tournament final in as many weeks, winning the previous two. After easily winning the first set, Zverev won the second set and was up a break in the third set before a rain delay interrupted the match. However, after the delay, Nadal would go on to win 5 straight games to seal the victory.^[11] This was his 8th Italian Open title and overall record-extending 32nd Masters 1000 title. It is also his 78th career title, making him the 4th most title holder in the Open Era, passing John McEnroe whom he was tied with before this tournament. He became world no. 1 again after relinquishing it for only one week.

French Open

Nadal needed to win the French Open to retain his World No. 1 ranking. He began the tournament by defeating Simone Bolelli, Guido Pella, Richard Gasquet, and Maximilian Marterer all without losing a set en route to the quarterfinals. His opponent in the QF, clay-court specialist Diego Schwartzman, took the first set and became the first person to win a set against Nadal in the tournament since Djokovic defeated Nadal in straight sets in the 2015 French Open, thus ending Nadal's 37 sets win streak at the French Open. Nadal won the next three sets and continued his form by defeating Juan Martín del Potro in the semifinals in straight sets. In the final, he met Dominic Thiem, the only man to beat Nadal on clay in 2017 and 2018. Nadal dispatched the Austrian in three sets, never losing more than 4 games in a set, to win his record-extending 11th French Open title, equalling the record for most titles won in a single major by either men or women held by Margaret Court with her 11 titles in the Australian Open. His win was also his 17th major singles title, which is 2nd on the men’s Open Era list behind only Roger Federer.^[12]

Exhibition matches

Nadal's schedule for 2018 included the Queen's Club Championships, but in the week before he chose to withdraw from the tournament to be able to recover after the clay court season.^[13] He chose to participate in the Hurlingham Tennis Classic, an exhibition tournament played from 26 to 29 June at the Hurlingham Club, in London, to get some preparation for the following week's Wimbledon Championships. He first played Matthew Ebden, winning the match in two tight sets, and on the tournament's last day he played Lucas Pouille – this time losing in straight sets.

Wimbledon

Despite being ranked ATP No. 1 coming to Wimbledon, Nadal was seeded 2nd according to their special formula (behind defending champion Roger Federer). He successfully replicated his previous result of reaching the 4th round by defeating Dudi Sela, Mikhail Kukushkin, and rising-star Alex de Minaur all in straight sets, guaranteeing himself the No. 1 ranking after Wimbledon. Nadal booked his first quarterfinal spot since reaching the Wimbledon final in 2011 by beating Jiří Veselý in straight sets. He proceeded towards the semis after outlasting Juan Martín del Potro in a five-set thriller which lasted nearly 5 hours. In the semifinals, he suffered a heart-breaking five set loss to Djokovic after squandering three set points in the third set, that would have put him at a 2-1 set lead after that set, with the match lasting two days due to Wimbledon's 11pm curfew.^[14] However, a semifinal at Wimbledon indicated his best performances here since 2011. This semifinal match was the second longest ever, the longest was Kevin Anderson vs John Isner which the two had played before the Nadal-Djokovic match earlier on that day.

Canadian Open

Nadal opened his hard court season campaign by beating Benoît Paire in straight sets. In the round of 16, he beat resurging former World No. 3 Stan Wawrinka in straight sets, and followed this with a comeback victory against World No. 7 Marin Cilic, whom he lost to after retiring in the Australian Open, in the quarterfinals. He remained solid and defeated in-form NextGen player Karen Khachanov in straight sets to reach his first hard court final of the year. Nadal faced off against Stefanos Tsitsipas in the final and won in straight sets, winning his 4th Rogers Cup title and extending his record Masters 1000 titles to 33 titles.^[15] It was his first victory at a hard court Masters 1000 tournament since 2013 Western & Southern Open. He also became the 4th male player to win 80 career singles titles.

US Open

Having not played since his victory in Canada due to withdrawing from Cincinnati, Nadal was seeded No.1 at the US Open, where he was the defending champion. In the first round, Nadal faced compatriot David Ferrer, who was playing in his last grand tournament. In the last grand slam match of his career, Ferrer retired with a foot injury in second set. In the second round, Nadal faced Canadian Vasek Pospisil, who he defeated easily in straight sets. In the third round, Nadal faced Russian Karen Khachanov, who pushed Nadal hard before he managed to win in four tight sets. His next opponent was Georgian Nikoloz Basilashvili, whom he defeated in four sets. This marked the first year since 2011 that Nadal had reached the QF of all four majors. In his quarterfinal match, Nadal faced World No. 9 Dominic Thiem, whom he defeated earlier in the year in the French Open final. In an epic match, Nadal managed to seal the victory in the fifth set tiebreak, after having lost the first set 0-6. Nadal went on to then face Juan Martin del Potro, in a rematch of the previous year's semifinal which Nadal had won in four sets. However, Nadal retired after going down two sets to love due to a right knee injury.^[16] On 19 September, Nadal withdrew from the Asian tournaments at Beijing and Shanghai to fully recover from the injury.^[17]

Paris Masters

Nadal was scheduled to return from knee injury hiatus in the Paris Masters, but withdrew from an abdominal injury suffered during a training session. In that process, he also lost his world No. 1 ranking to Novak Djokovic.^[18]

ATP Tour Finals

On November 5, Nadal announced his withdrawal from the ATP Finals due to the abdominal injury, and also citing an ankle injury on which he decided to undergo surgery.^[19] This marked the end of his 2018 season, having not played since retiring in the semifinals of the US Open.

Singles: 5 (5 titles)

Result	W–L	Date	Tournament	Tier	Surface	Opponent	Score
Win	1–0	Apr 2018	Monte-Carlo Masters, Monaco (11)	Masters 1000	Clay	Kei Nishikori	6–3, 6–2
Win	2–0	Apr 2018	Barcelona Open, Spain (11)	500 Series	Clay	Stefanos Tsitsipas	6–2, 6–1
Win	3–0	May 2018	Italian Open, Italy (8)	Masters 1000	Clay	Alexander Zverev	6–1, 1–6, 6–3
Win	4–0	Jun 2018	French Open, France (11)	Grand Slam	Clay	Dominic Thiem	6–4, 6–3, 6–2
Win	5–0	Aug 2018	Canadian Open, Canada (4)	Masters 1000	Hard	Stefanos Tsitsipas	6–2, 7–6(7–4)