A general view shows the center court of the Monte Carlo Country Club during the match between Steve Johnson of the US and his compatriot John Isner in Monaco Monday. — Reuters MONTE CARLO, Monaco — John Isner defeated fellow American Steve Johnson 6-4, 6-4 to win his first career match at the Monte Carlo Masters Monday as Latvian 13th seed Ernests Gulbis fell 6-1, 6-0. Isner, seeded 15, has only ventured onto European clay this early in a spring once before in a career which began eight years ago. But a defeat in the 2013 first round did little to boost confidence for the self-confessed USA homebody who feels out of his depth culturally in Europe and prefers to stay on his side of the Atlantic whenever possible. Gulbis refused to bow to stress as the laid-back Latvian exited timidly, a 6-1, 6-0 first-round victim of Austria's Andreas Haider-Maurer. The admittedly slumping world No. 17 suffered his eighth loss from nine matches played this season, which began with a shoulder injury carried over from 2014 which disrupted his 2015 preparation. Gulbis lasted for less than an hour against Heider-Maurer, who plays Australian Bernard Tomic in the second round at one of the most picturesque venues in tennis. Elsewhere in the first round, Spanish 12th seed Roberto Bautista Agut began with a 6-0, 6-2 hammering of German Benjamin Becker, while 2013 semifinalist Fabio Fognini of Italy defeated Poland's Jerzy Janowicz 6-3, 6-1. Alexandr Dolgopolov stopped Croatian teenager Borna Coric 7-5, 5-7, 6-2 in two and a quarter-hours; Joao Sousa of Portugal beat Edouardo Roger-Vasselin of France 6-1, 3-6, 6-0 as the tournament mourned the death Sunday after illness of former tournament director Patrice Dominguez. Kerber out-lasts Keys In Charleston, Angelique Kerber ended her WTA dry spell with a gritty three-set victory over rising US talent Madison Keys Sunday for the Charleston claycourt crown. Kerber, a former world number five, battled back from 4-1 down in the third set to defeat 20-year-old Keys 6-2, 4-6, 7-5. The 27-year-old German withstood 49 winners from Keys, belting a modest 17 winners herself but keeping mistakes to a minimum with just 21 unforced errors. “I feel great,” said Kerber, who broke Keys for a 6-5 lead in the final set, and polished off the win by holding her serve at love. “Madison is a great player and she played very well today so I think both of us are champions,” the German said. With Sunday's win she's projected to jump two places in the rankings to 14th. Sock sinks Querrey American Jack Sock won his first ATP singles title defeating compatriot Sam Querrey 7-6(9), 7-6(2) in the final of the US Men's Clay Court Championship in Houston Sunday. It was the first time since 2003, when Andre Agassi defeated Andy Roddick, that two Americans faced each other in the Houston final. — Agencies