ARLINGTON, Texas (AP) Rangers manager Ron Washington expected Justin Grimm to hit some bumps in the road during his rookie season.
The 24-year-old Grimm certainly struggled Tuesday night against Kendrys Morales and the Seattle Mariners.
Morales homered twice and tied a career high with six RBIs, and Grimm gave up three home runs in all as Texas lost 9-2.
"When talking about youth on the mound, you're going to get inconsistency," Washington said. "We have to get past the inconsistency."
Grimm (7-6) leads American League rookies in wins but is in the midst of a rocky stretch. In his last six starts, he is 2-3 with a 9.31 ERA and has pitched past the sixth inning only once.
Against the Mariners, Grimm allowed six runs and seven hits in four innings. He was chased in favor of Ross Wolf after Morales hit his second homer.
"I'm just taking it and learning," Grimm said. "I need to execute my pitches, get outs and win ballgames. When I don't, stuff happens."
Morales had a solo home run in the first and a three-run shot in the fifth off Grimm. Seattle's designated hitter added a two-run single in the sixth to help the Mariners win for the first time at Texas this season.
After hitting just one homer in June, the switch-hitting Morales broke out in a big way with the 10th multihomer game of his career.
"He lost his stroke there a little bit," Mariners manager Eric Wedge said. "I think it's because he has been trying to do too much. But he's a good hitter who can do a lot of damage."
Joe Saunders (6-8) won for the first time in eight regular-season starts at Rangers Ballpark. The left-hander allowed two runs one earned and struck out five in 6 2-3 innings.
Raul Ibanez, who hit 10 homers in June, had a solo shot for his 20th homer of the season as the Mariners opened a six-game road trip.
Grimm retired the first two batters of the game before Ibanez lined a 2-1 pitch over the fence in the right. Three pitches later, Morales followed with a solo drive to make it 2-0.
"Their big bats in the order didn't miss," Washington said.
Texas' Leonys Martin dropped down a bunt single leading off the third to extend his hitting streak to 15 games, the longest active run in the majors. Martin scored two batters later on Elvis Andrus' single.
After Dustin Ackley had a run-scoring double in the fourth to push the lead to 3-1, the Mariners scored three runs in the fifth.
Nick Franklin led off with a single and Ibanez reached on Ian Kinsler's error at second base to set the stage for Morales. He hit the first pitch from Grimm into the seats in right, extending Seattle's lead to 6-1.
"I just left some pitches up and they got a hold of them," Grimm said. "I just didn't execute pitches. I didn't do my job."
It was Morales' first multihomer game since last Aug. 8 against Oakland.
Morales, who went 3 for 5, capped his big game with a two-run single in the sixth to make it 8-1. It was the fourth time he had six RBIs in a game. He last drove in six on July 30, 2012, against Texas.
Saunders, who won the 2012 AL wild-card game at Rangers Ballpark with Baltimore, came in 0-7 with a 9.91 ERA in the regular season at Texas. The left-hander was coming off his shortest start of the season, when he allowed six runs in 1 2-3 innings June 25 against Pittsburgh.
"This place has torn me up a few times," Saunders said.
Saunders got double-play grounders to end the fifth and sixth. After he recorded the first two outs of the seventh, Andrus and Nelson Cruz had consecutive singles to chase Saunders.
NOTES: Texas RHP Colby Lewis (elbow) threw 37 pitches in the bullpen and is expected to have another bullpen session Thursday. ... Rangers opening-day starter Matt Harrison, out since April while recovering from back surgery, threw from 120 feet. ... Ackley was back in the starting lineup after missing Sunday's game with a sprained left thumb. ... Texas DH Lance Berkman (sore right knee) missed his fourth straight game. Berkman said he hopes to return to the lineup Wednesday night. ... Rangers radio announcer Eric Nadel missed most of the game because of laryngitis. Texas' lead radio voice called the first inning before leaving. ... The Rangers outscored the Mariners 23-3 in a three-game sweep April 19-21.