Brian Baker of the U.S. and Nikola Mektic of Croatia kicked off their grass-court season with success on Tuesday, beating Frenchmen Lucas Pouille and Gilles Simon 7-5, 6-3 to move into the quarter-finals of the Mercedes Cup in Stuttgart.

Baker and Mektic, champions on the indoor hard courts in Memphis and the outdoor clay courts of Budapest already this season, won 82 per cent of their first-serve points to advance in 64 minutes.

They will next face second seeds Jamie Murray and Bruno Soares, who advanced by walkover. Treat Huey and Robert Lindstedt had to withdraw because of a back problem for Huey, and no alternate doubles team was available to take their place.

In other doubles action, fourth seeds Oliver Marach and Mate Pavic advanced 7-6(3), 6-7(9), 10-6 against German wild cards Andre Begemann and Jan-Lennard Struff. Marach/Pavic will meet Nicholas Monroe of the U.S. and Artem Sitak of New Zealand, who edged Steve Johnson of the U.S. and Feliciano Lopez of Spain 7-5, 7-6(4).

Stuttgart fans will be treated to a battle of close friends on Wednesday when Tommy Haas and Roger Federer square off in the second round of the Mercedes Cup.

The 39-year-old Haas advanced past Frenchman Pierre-Hugues Herbert 6-3, 4-6, 7-5 on Tuesday to get another chance at Federer, the top seed who received a first-round bye.

“I felt I served well… we both struggled a little with the returns. We used our chances when we got them. The key part to winning the match was getting that one more break point than my opponent. I’m obviously very pleased and anything can happen on grass,” said Haas, who converted two of three break points.

The 35-year-old Federer leads their FedEx ATP Head2Head series 13-3 but they haven’t played in more than three years, since the 2014 BNP Paribas Open in Indian Wells. Haas last beat Federer during the final of the 2012 Gerry Weber Open in Halle for his second grass-court crown. He also won Halle in 2009.

“We have known each other for a very long time,” Haas said of Federer. “We started to get closer around the time when my fiancée and his wife became friendlier. Then we had kids and started to hang out much more. We used to have the same agent, Tony Godsick, who is a very close friend of mine, so it was always an easy connection. [Federer] is a first-class guy. I have great times with him and I am happy to call him my friend.”

Haas, who plans to retire after this season, is making his seventh and final appearance in Stuttgart. He also advanced to the second round in 2015, the first year the tournament had transitioned from clay to grass.

Herbert’s countryman Benoit Paire was victorious in his Stuttgart opener, ousting eighth seed Viktor Troicki of Serbia 6-4, 6-4. Paire landed only 45 per cent of his first serves but claimed 55 per cent of his second-serve points to advance. The 6’5” 28 year old has emerged as this season’s ATP World Tour “Iron Man” so far.

Stuttgart marks the 18^th ATP or Grand Slam tournament Paire has competed at this season – the most events possible based on the calendar. The Frenchman improved to 18-17 this season and will next play German qualifier Peter Gojowczyk, who beat Georgian Nikoloz Basilashvili 2-6, 6-3, 6-1.

Read More: Federer: ‘There Are No More Breaks Now’

Two-time finalist and home favourite Philipp Kohlschreiber moved into the second round when former World No. 8 Marcos Baghdatis retired after losing the first set 6-1. Kohlschreiber is looking to return to the Top 50 of the Emirates ATP Rankings after falling out on Monday for the first time since October 2011. He will next meet American Steve Johnson.

Spaniard Feliciano Lopez improved to 4-2 against Gilles Simon in their FedEx ATP Head2Head series with a 6-3, 6-3 victory against the seventh-seeded Frenchman. The 35-year-old Lopez will meet Frenchman Jeremy Chardy, who outlasted German and 2016 Halle champion Florian Mayer 7-6(3), 4-6, 7-6(1).

Pole Jerzy Janowicz, who reached the Wimbledon semi-finals in 2013, set-up a second-round meeting against second seed Grigor Dimitrov after prevailing against Russian Andrey Kuznetsov 6-4, 3-6, 6-3 in one hour and 59 minutes. The 26-year-old Janowicz saved six of seven break points.

Crushed brick has been replaced by mown lawns. Ribbed soles have been unlaced in favour of pimple-soled shoes. Baseline battles and lengthy rallies won’t be commonplace as knee-bending, dinks and sliced shots are now essential for success during the six-week grass-court swing.

World No. 1 Andy Murray was perfect on grass in 2016, with a 12-0 record (1.000), winning the two tournaments he entered: his fifth crown at the Aegon Championships (30-5 tournament record) and his second trophy at Wimbledon (53-9 event record).

The player Murray beat in both finals, Canada’s Milos Raonic, who brought on board three-time former Wimbledon champion John McEnroe for last year’s grass-court swing, went 10-2 (.833). The World No. 6 will be looking to add to his lone Grand Slam championship final appearance over the next five weeks.

France’s Nicolas Mahut, who is competing this week at the Ricoh Open, where he is a three-time champion (19-2 tournament record), had the third-best winning percentage on grass courts in 2016, going 8-2 (.800).

View Best Grass-Court Performers In 2016

Overall in ATP World Tour history, since 1973, Roger Federer leads the FedEx ATP Performance Zone for career grass-court matches with a 152-23 mark and 15 titles (.869 per cent). Federer has clinched seven Wimbledon titles and the same number at the Gerry Weber Open in Halle.

John McEnroe is second overall in the all-time list with a 121-20 grass-court record and eight titles (.858), followed by Murray, who has a 102-17 grass-court record and eight titles (.857). Bjorn Borg, who won Roland Garros and Wimbledon back-to-back for three straight years (1978-80) and the first player to wear pimpled grass-court soles, compiled a 61-11 mark, including six Wimbledon titles (.847). Pete Sampras, who won 10 titles and ended his career with a 101-20 tally (.835), is fifth overall.

View Best Grass-Court Performers According To FedEx ATP Performance Zone

You have got to win small to win big.

Pablo Carreno Busta is enjoying a breakout season, boasting a career-best Emirates ATP Ranking of No. 17 this week, following his strong run to the Roland Garros quarter-finals. For good measure, he is also ranked No. 18 in doubles, which is only one spot off his career best that he achieved in January after reaching the Australian Open doubles semi-finals.

His climb up the Emirates ATP Rankings very much mirrors his playing style – patient and steady. Carreno Busta has been ranked in the Top 100 in singles for 201 consecutive weeks since 5 August 2013. This is his sixth week in the coveted Top 20.

But just how dominant has he been this season compared to the past couple? What are the metrics that have underpinned his rise?

An Infosys ATP Beyond The Numbers analysis of Carreno Busta’s 2015, 2016 and 2017 seasons identifies small gains over long periods of time.

Carreno Busta: Points Won 2015-2017 Seasons

In 2015, Carreno Busta actually lost more points than he won, finishing the season just outside the Top 50 at No. 67. This is actually typical for players in the 50-100 range. They look successful, but overall they experience a point deficit for the season.

The 25-year-old Spaniard leapt to No. 30 at the end of 2016 by winning just 216 more points than he lost. That represented just 2.2 per cent of his total points (9,774) for the season. From 2015 to 2017, including during the past two weeks at Roland Garros, Carreno Busta has played 22,119 points. He has won just 395 more points than he has lost, representing 1.7 per cent of his total points.

Improvement this year has been powered by making a lot more first serves.

Carreno Busta’s Serving Improvement

Carreno Busta is impressively ranked 11th in the ATP Stats Return LEADERBOARDS, powered by Infosys Nia Data, and 31st on the Serve Leaderboard. One area the Spaniard can improve on when serving is making more first serves on break points.

He is ranked fourth best in 2017 in first serves made at 68 per cent, which was the exact same number he put up at Roland Garros during his quarter-final run. But when facing break point this year, that 68 per cent average has dropped to just 62 per cent (155/252).

As wildly successful as Carreno Busta is, with a Top 20 ranking and more than four million dollars in career prize money, he has barely won more matches than he has lost (102-98), and he has won just 50 per cent of the total points in his career. His ranking speaks to dominance on tour, but the metrics suggest a far more level playing field.

Carreno Busta is definitely on a collision course with a Top 10 ranking. A point here and there will be all that it takes to achieve it. #NextGenATP German Alexander Zverev is currently No. 10, winning 52 per cent of his points in 2017 – the same as Carreno Busta.

The near future looks bright for the Spaniard as well. He has zero points to defend from last year’s grass-court season, so he may get to single digits sooner rather than later.

See Who’s Pushing Carreno Busta In The Emirates ATP Race To London