Darvish, a two-time Japan League Most Valuable Player with the Nippon Ham Fighters, was tagged for five runs in the first two innings against the Mariners before the Texas Rangers rallied for an 11-5 victory.
Struggling with his command, Darvish gave up four runs in a 42-pitch first inning and surrendered another run in the second frame -- when he gave up two doubles.
Overall Darvish allowed five runs on eight hits and four walks. He struck out five, and four of the hits came against Japanese batters. Ichiro Suzuki was 3-for-4 off him, and Munenori Kawasaki was 1-for-2 with a walk.
It was a less than dazzling beginning for a player acquired prior to this season for a total of $107.7 million -- $56 million for his six-year deal and the rest just for the right to negotiate with him.
However, Darvish settled down to pitch 5 2/3 innings, departing with two outs in the sixth to a standing ovation with the Rangers leading 8-5.
Nelson Cruz hit a three-run homer in the third for Texas. Mitch Moreland and Josh Hamilton both homered in the fourth and Ian Kinsler added a three-run blast in the eighth.
"Just like you saw tonight, those guys are incredible. Just incredible," Darvish said of the offensive firepower demonstrated by his new teammates.
Darvish opened his highly anticipated major league debut by walking Chone Figgins on four pitches.
He struck out Dustin Ackley, but Suzuki lifted a high ball into left field for a single.
Justin Smoak singled to right to load the bases and Kyle Seager singled to center to drive home two runs.
A walk to Michael Saunders reloaded the bases, Miguel Olivo's single scored another run before Darvish walked Kawasaki to force home the fourth run of the first frame.
Rangers reliever Scott Feldman was warming up in the bullpen when Darvish got out of the inning by striking out Brendan Ryan and inducing Figgins to ground out.
RBI singles by Michael Young and Cruz brought home two runs for the Rangers in the bottom of the first.
Seattle responded in the top of the second inning with a one-out double by Suzuki, who scored on Seager's double.
Darvish showed his determination, however, as he retired 13 of 16 batters the rest of the way -- including one stretch of 10 straight -- before he was replaced by Alexi Ogando.
"Today was more of a mental battle for me," Darvish said. "I had to stay in there and battle with what I had. I thought whatever I had, if I could string those zeroes together, the offense would come back."
Darvish admitted he couldn't harness his energy in the first inning. Rangers manager Ron Washington knew what the problem was and opted to let his new star try to work through it.
"I wasn't going to go snatch him in the first inning," Washington said. "It seemed like he just couldn't get a hold of his emotions. He was over-amped."
Darvish was already settling after the second inning.
Cruz tied the game in the third with his three-run homer to left field. Moreland belted a two-run homer in the fourth, which was followed by Hamilton's massive solo homer to center.
"Our goal is to do what it takes to win the game and tonight that meant score runs," Kinsler said. "We were able to turn that up and put runs up for him.
"In the first inning to get those two runs to answer and put us close was huge. He felt like he was back in the game. He got a breather."
When Washington did finally head out to the mound to tell Darvish his day was done, the crowd of 42,003 at Rangers Ballpark sent him off to a chant of "Yu-u--u".
Rangers president Nolan Ryan was impressed with the fortitude Darvish displayed after his tough first inning.
"I didn't give him that much of a chance for the pure number of pitches he threw in the first inning and the fact that he didn't have a feel for anything," Ryan said. "He hung in there and looked like a totally different pitcher at the end than he did at the start.
"I look at it as a very positive outing."
