In week two of the grass-court season, the ATP Tour heads to ATP 500 tournaments in London and Halle. Top seed Stefanos Tsitsipas prepares to make his debut at the Fever-Tree Championships, while nine-time champion Roger Federer will be searching for a 10th trophy at the NOVENTI OPEN. Here are 20 things to watch from the ATP 500 events:

10 Things To Watch In London/Queen’s Club

1) Fantastic Field: The top players in tennis continue the grass-court season as they head to ATP 500 events in London and Halle. At the Fever-Tree Championships, top seed Stefanos Tsitsipas, 2015 finalist Kevin Anderson, and defending champion Marin Cilic are all in action. Also, Andy Murray returns to the ATP Tour for the first time since the Australian Open, in the doubles draw.

2) Greece Lightning: One year ago, Tsitsipas was at a career-high ranking of No. 35. Since then, he has achieved a new career-high ranking 10 more times, cresting to his current peak of No. 6, having earned three ATP 250 titles. This week’s No. 1 seed, who has reached two ATP Masters 1000 finals and made a run to the 2019 Australian Open semi-finals, is seeking his first grass-court title.

Read Tsitsipas: ‘I Would Love To See Myself Playing In The O2’

3) Comeback Kevin: No. 2 seed Anderson returns to action after injury has kept him off the Tour since a quarter-final loss to Roger Federer in Miami in March. Anderson has been limited to just three events in the first five months of the season, but will try to come back strong during the grass-court swing. The South African made his second Grand Slam final on the lawns of Wimbledon last year.

4) Champ Cilic: Defending champion Cilic holds a superb 29-9 win-loss record at The Queen’s Club. The Croat won the first of his two London titles in 2012 and also reached the championship match in 2013 and 2017. Cilic, who owns a 9-8 tour-level record this season, will try to kickstart his year after falling to No. 15 in the ATP Rankings, his lowest position since 2014.

5) Determined Delpo: Juan Martin del Potro contested just one event in the first four months of the season. But the Tower of Tandil owns a 5-2 record in his two most recent events, reaching the quarter-finals in Rome and the fourth round at Roland Garros.

6) Russian to the Top: Daniil Medvedev aims to join his compatriot Karen Khachanov in the Top 10. The 23-year-old Russian started the season 25-7 and stands at a career-high ranking of No. 13. However, Medvedev will be aiming to recapture his best form in London after losing each of his past five tour-level encounters.

7) We The North: Canada boasts three Top 25 players, and they are all at The Queen’s Club this week. Top-ranked Canadian Milos Raonic is seeded sixth and has a run to the final in 2016 on his resume. Hot on his heels in the ATP Rankings are #NextGenATP stars Felix Auger-Aliassime and Denis Shapovalov, who are the two highest-ranked under-21 players other than Tsitsipas.

8) Wild Ones: Former champion Feliciano Lopez was awarded a wild card into the main draw. The 37-year-old Spaniard won the title after beating Cilic in the 2017 final, three years after falling to Grigor Dimitrov in the 2014 championship match. Brits Daniel Evans and 20-year-old Jay Clarke picked up the other two wild cards. Evans has lifted back-to-back trophies at ATP Challenger Tour grass-court events in Surbiton and Nottingham this month.

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9) Sweet Successes: Dimitrov joins Cilic and Lopez to complete the trio of former champions in the singles field. Also, 2007 finalist Nicolas Mahut clinched a spot in the 2019 main draw after successfully navigating his way through the qualifying draw.

10) More of Murray: No. 1 seeds Juan Sebastian Cabal and Robert Farah enjoyed an impressive clay-court season, lifting an ATP Masters 1000 trophy in Rome and making the Roland Garros semi-finals. This week, they have an eye-catching opener against the wild-card team of Lopez and Murray. British hero Murray, a five-time singles champion at The Queen’s Club, returns to action for the first time since the Australian Open in January.

10 Things To Watch In Halle

1) Fantastic Field: The top players in tennis continue the grass-court season as they head to ATP 500 events in Halle and London. At the NOVENTI OPEN, nine-time champion Roger Federer, two-time finalist Alexander Zverev, and defending champion Borna Coric will be in action.

2) Going for 10: Federer, who has a stellar 63-7 record in Halle, aims for his first double-digit title haul at a single event this week. The Swiss star has won nine times both here and at his home event in Basel. Rafael Nadal is the only player in the Open Era to reach double-digit titles at a single event, with 12 Roland Garros titles and 11 trophies in Monte-Carlo and Barcelona.

Read Federer: ‘The Pressure Is High For Me Too’

3) Surging Sascha: Zverev started the season 15-10 but has won eight of his past 10 matches since then, claiming his first title of 2019 in Geneva before reaching the Roland Garros quarter-finals for the second straight year. Zverev will try to shake off an opening-match loss in Stuttgart by returning to an event where he has experienced success; he was runner-up in Halle in 2016 and 2017.

4) Borna Winner: Coric came into last year’s event with just two wins out of nine Tour-level matches on grass, but stunned Federer in three sets in the final to claim the biggest title of his career to date. Coric went on to lose his only other grass-court match of 2018, to Daniil Medvedev at Wimbledon, but he is off to a good start on grass in 2019, making the ‘s-Hertogenbosch semi-finals last week.

5) Top 10 Time: Karen Khachanov broke into the Top 10 of the ATP Rankings directly after reaching his first Grand Slam quarter-final at Roland Garros, becoming the first Russian in the Top 10 since Mikhail Youzhny during the week of 7 February 2011. Khachanov is 14-14 so far this year.

6) Gael Force: Gael Monfils started the year a career-best 15-3, winning his 8th ATP Tour title in Rotterdam in the process, before injuries took him out of ATP Masters 1000 events in Indian Wells, Miami and Monte-Carlo. The French No. 1 is now back in business, and recently reached the second week at Roland Garros for the eighth time.

7) Fabulous French: Jo-Wilfried Tsonga, who has a wild card this week, has risen from No. 239 at the end of an injury-plagued 2018 to No. 77 this week, and has already hoisted a singles title in 2019, in Montpellier. Tsonga will face his compatriot Benoit Paire in the first round; Paire is one of eight players to have won multiple singles titles this year, triumphing in Marrakech and Lyon.

8) Home Team: Zverev is part of a German contingent which will try to claim the Halle title for their country for the first time since Florian Mayer in 2016. 2011 champion Philipp Kohlschreiber is back in the draw, Jan-Lennard Struff is surging after a semi-final showing in Stuttgart last week, and Peter Gojowczyk and 18-year-old Rudolf Molleker are in with wild cards.

Read Federer Handed Tough Path In Quest For 10th Halle Trophy

9) Qualies Quality: Another German, 223rd-ranked Mats Moraing, has joined the above group after successfully making it through qualifying to reach his first Tour-level match. 2015 Halle finalist Andreas Seppi of Italy is also back in the main draw after navigating the qualifying rounds.

10) Doubling Up: Two-time defending champions and No. 1 seeds Lukasz Kubot and Marcelo Melo aim for a Halle hat-trick, having beaten Alexander Zverev and Mischa Zverev in the past two finals. Joining the Zverev brothers as home-country contenders are the newly-crowned Roland Garros titlists Kevin Krawietz and Andreas Mies, who are seeded No. 4 in their tournament debuts.