With their edge for first place in the American League East game set at Safeco Field.
After taking Friday's opener for their fifth win in six games, the Red Sox had their lead over the Yankees in the division cut in half due to a 5-4 defeat to the Mariners. Ichiro Suzuki and Casper Wells homered during Seattle's five-run first inning, but the Mariners had to hold on for a 5-4 victory.
Mike Carp added a two-run single in the opening inning for Seattle, which rebounded from Friday's 6-4 loss that was its fifth in seven games.
After Hernandez pitched a scoreless seventh, Boston slugger David Ortiz nearly hit a game-tying homer off Jamey Wright in the eighth. But Wright managed to keep the Red Sox off the scoreboard and Brandon League worked the ninth for his 28th save.
Josh Beckett (9-5) took the loss after allowing all of the Mariners' runs, and lasted five innings.
He had trouble recording outs early in his outing. Suzuki began the bottom of the first inning with his second homer of the season, a blast to right field, and Franklin Gutierrez followed with a single.
"It was great to see us come out there and be aggressive and jump on them early, especially against a guy like Beckett," said Mariners manager Eric Wedge.
Seattle snapped a five-game losing streak against Boston with the triumph.
Boston's Tim Wakefield has put forth three unsuccessful attempts to earn his 200th career victory, and a fourth go-around will take place this afternoon. Despite not getting a win in those last three outings, all three have fallen under the category of quality starts. The knuckleballer is 6-4 this season with a 4.92 ERA.
Wakefield is 1-0 against the Mariners this season, but he is he has allowed eight runs in 12 innings against the squad. The veteran is 5-10 lifetime against Seattle with a 4.32 ERA.
Expected to get the ball for Seattle is Charlie Furbush, as he is 2-4 with a 4.46 ERA. The lefty struggled in his last start, lasting less than five innings while allowing seven runs to the Rangers. He has permitted 47 hits in 42 1/3 innings of action.
The only previous career appearance for Furbush against the Red Sox came in relief earlier this season, and he pitched five shutout innings of two-hit ball in that affair.
The Mariners placed first baseman Justin Smoak on the 15-day disabled list Saturday. Smoak was hit in the face by a ball on a bad-hop grounder in the second inning of Friday's game. An X-ray revealed that he has a non-displaced fracture on his nose and a hairline fracture in his left cheek.