Roger Federer has on Monday returned to No. 1 in the ATP Rankings for the 309th week of his career, after Rafael Nadal was beaten in last week's Mutua Madrid Open quarter-finals. The Swiss begins his fifth stint at the summit of men's professional tennis at the age of 36 years, nine months.
Federer first became No. 1 at the age of 22 on 2 February 2004, spending 237 consecutive weeks there until 17 August 2008. He returned to the top spot for 48 weeks from 6 July 2009 to 6 June 2010, then 17 weeks between 9 July 2012 and 4 November 2012 and most recently from 19 February this year, for six weeks.
Federer, who is scheduled to return at the MercedesCup in June, has compiled a 17-2 record on the 2018 season with trophies at the Australian Open (d. Cilic) and the ABN Amro World Tennis Tournament (d. Dimitrov). He also finished runner-up to Juan Martin del Potro at the BNP Paribas Open in March.
Nadal, however, can reclaim the top spot on 21 May with a record eighth title this week at the Internazionali BNL d'Italia in Rome.
No. 7 Kevin Anderson, +1
The best start to a season for Kevin Anderson continued at the Mutua Madrid Open as the South African made his first ATP World Tour Masters 1000 semi-final. The 31-year-old had been 0-10 in Masters 1000 quarter-finals but outplayed Serbian Dusan Lajovic to reach the final four in Madrid.
Anderson's reward is another career-high in the ATP Rankings. Before 2018, the South African had spent only one week in the Top 10 (12-18 October 2015). But already this year, Anderson has spent 11 weeks (since 19 February) among the game's elite.
No. 15 Diego Schwartzman, +1
Diego Schwartzman matched his career-high ATP Ranking by making the third round in Madrid (l. to Nadal). The 13th-seeded Argentine beat France's Adrian Mannarino in straight sets before ending Feliciano Lopez's Madrid playing career. Lopez will be the Madrid Tournament Director next year.
No. 19 Kyle Edmund, +3
Brit Kyle Edmund celebrated one of the best wins of his career in Madrid, outplaying former No. 1 Novak Djokovic to beat the Serbian, who's on the comeback from right elbow surgery, in the second round.
The 23-year-old Edmund then backed up the big win by dismissing No. 10 David Goffin in straight sets to reach his first Masters 1000 quarter-final (l. to Shapovalov). Edmund is making his debut inside the Top 20 of the ATP Rankings.
No. 29 Denis Shapovalov, +14
The 19-year-old had not won an ATP World Tour match on clay before Madrid, but he more than showed he can compete on the European red clay. Shapovalov won four matches in the Spanish capital, including a 6-4, 6-4 victory against top countryman Milos Raonic, en route to the semi-finals (l. to Zverev).
Shapovalov, still only a teenager, has now reached two Masters 1000 semi-finals (2017 Montreal, l. to Zverev). The left-hander, who qualified for the inaugural Next Gen ATP Finals last year, is currently in second place in the ATP Race To Milan, behind Greek Stefanos Tsitsipas.