TORONTO -- The Blue Jays probably wish the rumors would've been true. Prior to Toronto's 5-1 loss to Seattle on Sunday, word around Rogers Centre was that Mariners left-hander Jarrod Washburn had been traded to the New York Yankees.

It was an odd situation for Blue Jays manager Cito Gaston, who would've had to change his starting lineup if Washburn wasn't going to be on the hill for Seattle. Only a couple hours before the game's first pitch, Gaston ducked back into Toronto's clubhouse to see what he could find out.

"If he was traded, their manager doesn't know about it," said Gaston, upon returning to the dugout.

That turned out to be bad news for the Blue Jays (53-52), who were unable to solve Washburn for eight innings, snapping the club's modest five-game winning streak in the process. If Washburn is indeed dealt to New York, Toronto's showing on offense certainly doesn't bode well for the rest of the year.

The Yankees and Jays have nine scheduled pairings down the stretch -- possibly giving Washburn a few more outings against Toronto. Already this season, the Seattle southpaw has gone 2-0 with a tidy 1.80 ERA in three appearances against the Jays, who fell to 10-18 versus left-handed starters this year.

"Washburn, he's pitched well against us," Gaston said. "For some reason, we do have trouble against left-handers. We'll just put this behind us and move on."

Washburn (5-9) was hardly the only issue facing the Blue Jays on this afternoon. Shaun Marcum continued to battle control issues in his second start off the disabled list and Toronto came up short on defense at one of the game's critical junctures. The result was a missed opportunity to sweep Seattle (39-65) in the three-game set.

"We made mistakes today," Gaston said. "When you make mistakes, it doesn't matter what team you're playing in the big leagues, they're going to beat you. We made some mistakes, as far as defense, and we didn't hit the ball well today."

Marcum (5-5) took the loss after surrendering four runs on six hits over 5 2/3 innings. Marcum dodged harm over the first five frames, blanking the Mariners along the way, before his location woes caught up with the right-hander in a four-run sixth inning for Seattle.

Ichiro Suzuki drew a leadoff walk against Marcum, who then watched a 1-0 pitch to Jose Vidro sail over the wall in right field for a two-run homer. That blast gave Seattle a 2-1 lead, though Marcum appeared to be on the verge of escaping further damage. With runners on the corners and one out, Marcum induced a ground ball off the bat of Jeremy Reed.

The chopper skipped toward Jays second baseman Marco Scutaro, who appeared primed to turn an inning-ending double play. Scutaro gloved the ball and, instead of quickly relaying the ball to shortstop John McDonald, applied an awkward tag on the runner headed to second base, leaving no time to nab Reed at first.

"I think he tried to get in front of the runner to make the tag," McDonald said, "and get away from him to make the throw to first. But, it looked from my angle like he got caught right with the runner, and couldn't free himself and make the transfer."

"It's just a mistake that he made," Gaston said. "That's going to happen. We thought it was a double play and I'm pretty sure he thought it was going to be a double play, too. It just didn't work out."

Seattle's next batter, catcher Kenji Johjima, ripped an offering from Marcum into right field for a two-run double, putting Toronto behind, 4-1. That ended the day for Marcum, who said he's had trouble locating his fastball down and away to right-handed hitters since coming off the DL after suffering a right elbow injury.

"When you can't throw that over for a strike, then they can sit on everything else." Marcum said. "If I locate my fastball, then everything else falls into place. It's just one of those things. I don't know what it is right now. I've just got to figure it out."

The Blue Jays also need to pinpoint why left-handers such as Washburn have given the club fits this season. Toronto's lone run against Washburn, who scattered four hits, came in the form of a rare home run off the bat off the light-hitting McDonald.

"We obviously have to give [Marcum] a little more support than that," McDonald said.