The St. Petersburg Open in Russia welcomes US Open champion Stan Wawrinka and three of the Top 10, while the Moselle Open in France features Dominic Thiem and a strong French contingent this week on the ATP World Tour

The 22-year-old became the ninth active player to win titles on three different surfaces in the same year in 2016 after Buenos Aires (clay), Nice (clay), and Acapulco (hard).

Mahut is the defending champion, and also won the title in 2013. Muller is 0-3 in career finals.

After losing to him in Rome, Roger Federer gets a rematch with Dominic Thiem on his favorite surface Saturday in Stuttgart.

Wozniacki returns from a foot injury…Wildcards were awarded to Pliskova and Brits Robson and Freya Christie…The slew of tournament withdrawals included former No. 1 Victoria Azarenka, Madison Keys, Petra Cetkovska, Irina Falconi, Monica Niculescu and Lesia Tsurenko…

“Yesterday I was feeling really tired, but my physio did a great job to get me ready for today’s match,” said Mahut, who also reached the doubles final. “It was a very tense first set, but after one-all he was missing some shots and I felt more and more confident.”

Rafael Nadal is back in a tournament final on grass.

Mahut qualified this week at the grass court Topshelf Open in ‘s-Hertogenbosch, and today beat defending champion and No. 3 seed Roberto Bautista Agut 6-2, 6-4 to reach the quarters.

The hodgepodge of seeds includes a former world No. 1 and Wimbledon champ and this year’s Wimbledon men’s doubles winner…Interesting starts for (7) Sock vs. the veteran Kuznetsov and the struggling (2) Karlovic vs. Ginepri…

Wildcards went to Azarenka and Brits Heather Watson and Johanna Konta…Pulling from the event were Svetlana Kuznetsova and Sorana Cirstea…Tough starts go to (5) Kerber vs. Riske, (4) Azarenka vs. Giogi, (8) Wozniacki vs. Stosur, and (2) Kvitova vs. Safarova…Returning former champs in the field are Wozniacki (2009) and Radwanksa (2008).

Potential tough starts for (1) Isner after a bye vs. compatriot (Q) Sock, and (2) Gulbis after a bye vs. the giant-killer Klizan…Isner has a 1-2 career record in Nice…This is the 30th anniversary of the Nice tournament…

Notes: Eight-time winner Rafael Nadal heads the field, and after a bye likely starts against Davydenko…(14) Marcel Granollers after a bye likely starts against The Worm…Wildcards went to Argentine Facundo Arguelleo, and Spaniards Roberto Carballes Baena, Inigo Cervantes, Daniel Gimeno-Traver…Withdrawing from the event were Pablo Andujar, Federico Delbonis, Richard Gasquet, Ivo Karlovic and Juan Monaco…David Ferrer is 0-4 in Barcelona finals…Fabio Fognini has never won a match in Barcelona (0-4)…Nadal beat Almagro in last year’s all-Spanish final…The two-time champ Bryan brothers are the top seeds in the doubles…Former singles champs in the field are Nadal (2013-11,’09-05), Robredo (2004), and Verdasco (2010).

Notes: One of the toughest 28-draw fields of the year with seven Top 10 players among the seeds, and more dangerous floaters than seeds…Challenging starts for (1) Serena after a bye vs. the Kleybanova-Makarova winner, (5) Jankovic after a bye vs. the Stephens-Safarova winner…

Frenchman Nicolas Mahut won a wild and wooly Hall of Fame Tennis Championships in Newport on Sunday, surviving his semifinal and final in the same day after rain on Saturday.

“She played the conditions much better than I did,” said Hampton, who is projected to rise to No. 25 in the rankings. “Honestly, I was surprised how she was even hitting the ball in the court [in the wind], and on top of that she was playing some very good tennis. She was very deserving of the title today…I have given myself like a two-hour time limit to sulk, basically the journey up to Wimbledon — I can sulk during that and maybe have a little chocolate, and then move on and get on with Wimbledon.”