SEATTLE – In the continuing challenge to develop young talent, the thought of pinch-hitting for Michael Saunders never crossed the mind of Seattle Manager Don Wakamatsu, even with Boston left-hander Hideki Okajima on the mound and three right-handed bats on the bench.

A day after breaking up Jon Lester’s no-hit bid with a two-run homer, Saunders came through again Sunday. His two-run single in the eighth inning gave Seattle the lead, Milton Bradley followed with a squeeze to score another run, and the Mariners rallied for a 4-2 victory against the Boston Red Sox.

Saunders entered the weekend with four hits all season against left-handers. He got two against Lester, including the go-ahead homer in the sixth.

A day later, he slashed a 1-2 pitch from Okajima into right field to score Jose Lopez and Justin Smoak, with third-base coach Lee Tinsley chasing Smoak almost to the dirt circle around home plate to get the lead run across.

Saunders is hitting .309 over his last 19 games.

“We’ve talked about the necessity for him to face left-handers and continue to play. That’s just more of the investment in his future,” Wakamatsu said.

The rally left the Red Sox wondering how a possible sweep in Seattle became a split of a four-game series as part of Boston’s 10-game West Coast swing.

There were plenty of issues for the Red to Sox ponder aside from Saunders. Okajima had an opportunity to stem Seattle’s eighth-inning rally if he makes the correct play on Casey Kotchman’s bunt, instead of hesitating and leaving everyone safe and the bases loaded.

“We always give them the option, if you’re not sure, get an out,” Boston Manager Terry Francona said. “From there it just, I don’t know if he didn’t have a handle, it didn’t look like there was a lot of urgency. They’re trying to give you an out and you’ll take it, and a lot of times good things don’t happen.”

There’s also Boston’s offense that scored four runs in the final three games of the series in Seattle, and without facing Seattle ace Felix Hernandez.

All those factors left the Red Sox frustrated, and eight games back of the Yankees in the American League East.

“We should be able to hit better against them,” David Ortiz said. “We’re not facing power pitching. We have the experience and ability to dominate.”

Seattle’s rally started innocently enough with singles by Lopez and Smoak. Kotchman’s bunt was botched by Okajima and Saunders’ hit gave Seattle a 3-2 lead.

Bradley, pinch hitting, followed Saunders with a squeeze for a base hit — done on his own — that scored Kotchman.

“Man on third, no outs, the last thing they probably expected me to do was bunt,” Bradley said. “I knew if I put it down there on the right side it was an easy run.”

Okajima (3-3) gave up two runs and five hits. One of the runs in the inning was charged to Daniel Bard, who allowed Lopez’s single.

Seattle’s rally ruined a strong effort by Boston starter Daisuke Matsuzaka, who struggled with major control problems early before settling down to be in line for his third straight win.

Matsuzaka was wild early, at one point in the third inning already over 60 pitches and with an equal number of strikes and balls. But he retired 10 of the final 11 batters he faced.