SEATTLE - Felix Hernandez didn't want to say anything about the sudden tightness that gripped his lower back in the third inning Saturday.

He didn't need to. Mariners manager Don Wakamatsu could immediately tell something was wrong.

"You could tell on his turn he was falling off because it was stiff," Wakamatsu said.

Seattle's ace had his string of 18 consecutive quality starts snapped in his shortest outing in nearly a year and he was outlasted by Texas lefty Matt Harrison in the Rangers' 6-3 win.

Hernandez (2-2) was already facing a 3-0 deficit when his back started tightening up in the third inning. He briefly went back into the Mariners' clubhouse to get some treatment and returned to pitch the fourth and start of the fifth inning.

But Josh Hamilton's homer leading off the fifth and a pair of walks ended Hernandez's day. The right-hander lasted just 4 1/3 innings, tagged for five runs and eight hits by the Rangers. It was the first time since May 9 last season that Hernandez failed to go at least five innings and it ended a string of quality starts dating to Aug. 1.

"Today was not my day. That's all," Hernandez said. "That was the first time I (felt) that in my career. I'll be OK. I'll be ready for the next one."

While Hernandez admittedly was not at his best, Harrison worked extra to earn his first victory of the season. The young left-hander threw a career-high 127 pitches, making it through six innings against the light-hitting Mariners. His victory made him the first Texas pitcher to record 14 wins in his first 31 games.

Harrison (1-1) escaped early jams with a pair of key double plays in the first and second innings, and wiggled free from major trouble when Seattle scored in the third and fifth. He gave up just two earned runs, struck out three and walked three. All seven hits he allowed were singles and he threw 81 strikes.

And beating Hernandez, a night after the Rangers outlasted Cliff Lee in a 2-0 win in 12 innings, wasn't lost on Harrison.

"It's a boost in confidence, especially against a pitcher like Felix," Harrison said. "We were able to go out there and swing the bats and make him go deep in counts."

Elvis Andrus added a two-run double misplayed by Seattle left fielder Milton Bradley, and Hamilton's fourth homer of the season helped the Rangers take the first two games of the weekend series.

Frank Francisco walked the first two batters in the ninth but recovered for his second save, one day after Neftali Feliz picked up his fourth save.

"Today was a big day for Harrison," Texas manager Ron Washington said. "We needed a grinder - for him to get us through six innings - and he did."

Instead of overpowering, Hernandez was ordinary. He struck out five but walked four, twice loaded the bases and got burned both times. It was his shortest start since lasting just four innings at Minnesota last May.

Hernandez had a nine-game win streak snapped in his last start at Kansas City and his streak of 18 straight quality starts was the third-longest in baseball since 2000. Now he's riding a two-game losing streak for the first time since last May, and the five earned runs raised his ERA from 2.23 to 3.10.

"I'm tough and I'm just going to go out there and battle and pitch my game," Hernandez said. "(There's) nothing I can do about this one, just get ready for the next one."

Hernandez didn't get many breaks. With the bases loaded and one out in the second, first baseman Casey Kotchman had a grounder from Julio Borbon take an awkward hop that dashed any hopes of an inning-ending double play. Borbon was out but Ian Kinsler scored.

Andrus then followed with a routine fly to left-center that was misplayed Bradley. Thinking center fielder Franklin Gutierrez was covering his gap, Bradley never broke on the ball. It fell behind him for a two-run double.

Wakamatsu said Bradley immediately took responsibility.

Hamilton's homer was just his fourth hit in 26 career at-bats against Hernandez. Justin Smoak and Michael Young added RBI singles.

Jose Lopez drove in two runs for Seattle and Bradley had an RBI infield hit.

NOTES: Wakamatsu said LHP Erik Bedard felt good after a 50-pitch bullpen session on Friday. Bedard, recovering from shoulder surgery, is likely facing one more bullpen before a simulated game and some minor league rehab appearances. ... Besides Harrison, Kevin Brown is the only pitcher in Rangers history with 13 wins in his first 30 games. Brown's 14th win came in his 33rd game. ... Gutierrez snapped an 0-for-13 slide with a bunt single in the fifth.