Unbeaten Japanese pitcher Yu Darvish improved to 4-0 in his first Major League Baseball season, striking out nine batters in seven innings for Texas in a 4-1 victory at Toronto. The 25-year-old right-hander threw 62 of his 97 pitches for strikes and continued a progression of looking more impressive with every North American start as the Rangers improved to 17-6, the best mark in the major leagues. \"The biggest thing is just getting used to the atmosphere of being in the major leagues,\" Darvish said through a translator. \"There\'s just a comfort, a feeling better, that has made me able to get better.\" The Rangers, who lead the American League West division by six games over Seattle after the first month of the six-month regular season, spent $107.7 million to obtain Darvish from the Nippon Ham Fighters. Darvish, a two-time Japan League Most Valuable Player, signed a six-year deal with Texas for $56 million and the rest of the money went to the Hokkaido-based Fighters just for ther right to negotiate with Darvish. Darvish made five starts before allowing his first North American home run, giving up a round-trip blast to the Blue Jays\' Edwin Encarnacion in the fourth inning, but the Japanese ace allowed only four hits over seven innings. \"I\'m certainly impressed with his work ethic,\" Rangers manager Ron Washington said of Darvish. \"I\'m impressed with the way he fits in my clubhouse. I\'m impressed with the way he interacts with his teammates. I\'m impressed by how quick he makes adjustments on the fly.\" Darvish has a 2.18 earned-run average, which is not bad for a pitcher who surrendered five runs in the first two innings of his Rangers career only three weeks earlier. \"I\'ve been impressed with his stuff,\" Washington said. \"He can sink it, he can run it, he can hop it, he can slow it down, he can make it quick, he can cut it, split it -- he can do everything with the baseball. \"It\'s just a matter of using that stuff at the proper time.\"