Roquebrune-Cap-Martin, France (SportsNetwork.com) - American John Isner moved on, while struggling Latvian Ernests Gulbis came up an open opening-round loser Monday at the Monte Carlo Masters, the first clay-court Masters event of the year.

The 15th-seeded 6-foot-10 Isner popped 13 aces to get past two-time NCAA singles champion and fellow American Steve Johnson 6-4, 6-4, while rising Austrian Andreas Haider-Maurer mauled the 13th-seeded Gulbis 6-1, 6-0 in 58 minutes at the famed Monte Carlo Country Club.

Gulbis is now a dismal 1-7 this year, including six tournament-opening losses.

"In practice I played very well," said Gulbis. "I'm lacking confidence now on the court for the match. I was in a great state of mind this week practicing."

Twelfth-seeded Spaniard Roberto Bautista Agut eased into the second round by pasting German Benjamin Becker 6-0, 6-2 on Day 2.

Additional first-round wins came for French qualifier Benoit Paire; Ukrainians Sergiy Stakhovsky and Alexandr Dolgopolov; German Philipp Kohlschreiber; Portuguese Joao Sousa; Italian Fabio Fognini; Belgian David Goffin; and Spanish qualifier Albert Ramos-Vinolas.

On Tuesday, second-round matches will come for world No. 1 Novak Djokovic, fifth seed and former runner-up David Ferrer and eighth-seeded U.S. Open champion Marin Cilic. The 2013 Monte Carlo champ and two-time runner-up Djokovic will be opposed by the aforementioned Ramos-Vinolas.

The high-flying Djokovic captured this year's first two Masters events, in Indian Wells and Miami.

Meanwhile, ninth-seeded Bulgarian star Grigor Dimitrov will play a first-round match against former top-10 Spaniard and 2010 Monte Carlo finalist Fernando Verdasco on Tuesday.

In the first all-Swiss final in 14 years on the ATP World Tour, Stan Wawrinka upset Roger Federer for last year's title here.

Rafael Nadal won an Open Era-record eight consecutive titles at this event from 2005-2012 and has a staggering 50-3 record in the tournament.