Madrid, Spain (SportsNetwork.com) - U.S. Open champion Marin Cilic and American John Isner were among Monday's first-round winners at the Madrid Open.

The ninth-seeded Croatian Cilic defeated Czech and recent Bucharest runner-up Jiri Vesely 7-5, 6-1, while the towering 16th-seeded Isner got past France's Adrian Mannarino 7-6 (7-2), 6-4 at the Magic Box in this clay-court Masters 1000 event.

Another seeded victor was No. 11 Spaniard Feliciano Lopez, who fought his way past German Benjamin Becker, 7-5, 3-6, 6-4.

Meanwhile, American Steve Johnson overcame Colombian qualifier Alejandro Gonzalez 4-6, 6-3, 7-6 (7-4) and American Sam Querrey held off Aussie qualifier Thanasi Kokkinakis 6-4, 6-7 (6-8), 6-3.

Also on Day 2, Italian Fabio Fognini handled Colombian Santiago Giraldo 6-2, 6-3; Portuguese lucky-loser Joao Sousa dismissed Pole Jerzy Janowicz 6-4, 7-5; Brazilian qualifier Thomaz Bellucci topped Frenchman Jeremy Chardy 6-4, 7-5; Italian qualifier Luca Vanni took out up-and-down Aussie Bernard Tomic 3-6, 6-4, 7-6 (7-1); and Belgian David Goffin overcame struggling Latvian Ernests Gulbis 3-6, 6-1, 7-5. Goffin should have his hands full with fourth- seeded U.S. Open runner-up Kei Nishikori in his next outing.

Some stars scheduled for action on Tuesday are fifth-seeded Milos Raonic, eighth-seeded Stan Wawrinka and 10th-seeded Grigor Dimitrov, who will take on American Donald Young in the round of 56.

The top seed for this French Open tune-up is Roger Federer, who enters the tournament after winning the inaugural Istanbul Open on Sunday. The 17-time Grand Slam champion won this Madrid title in 2009 and 2012, beating Rafael Nadal each time. He also won in 2006 when the tournament was played in the fall on hardcourts, and last played at the Magic Box in 2013, falling to Nishikori in the round of 16.

Nadal is also entered this week and is the third seed. He is the two-time defending champion and a four-time Madrid winner, beating Nishikori in last year's finale.

The former top-ranked Nadal will face the aforementioned Johnson in the round of 32.

Andy Murray is the other former winner in the draw. Seeded second this week, he won the 2008 title on a hardcourt.