Updated

In jeopardy of losing three straight for the first time game set at the Coliseum.

Toronto, which has lost back-to-back games five times since the All-Star break, is fading fast in the American League East where it is now 13 games off the pace and in fourth place in the standings, ahead of only Baltimore.

On Saturday the Jays produced just a single run and generated four hits in a 5-1 loss to Oakland. Edwin Encarnacion was responsible for knocking in the only run for the visitors, getting the job done in the first inning, but after that the Toronto bats fell pretty much silent. Picking up his first big league decision, Henderson Alvarez pitched well as he allowed just two runs -- one earned -- on seven hits over six innings. Unfortunately, Alvarez was also tagged with the loss due to his team's inability to produce a modest offense.

Over on the other side Gio Gonzalez, who had lost five straight appearances, stepped up and pitched a gem for the A's as he allowed just the one run on four hits, walking one and striking out nine as he survived a lackluster first inning. Andrew Bailey pitched a perfect ninth to preserve the win.

"In the first inning, it didn't look like he had his great stuff," A's manager Bob Melvin said of Gonzalez. "It looked like he had a different look in his eye when he came out for the next inning."

Josh Willingham accounted for a late pinch-hit two-run homer for the A's, winners of two straight and four of the last five, while Hideki Matsui posted two hits with an RBI and Ryan Sweeney also drove in a run for the hosts who are now 12 games under .500 and a distant 15 1/2 games out of contention in the American League West.

Toronto is set to go with yet another youngster this afternoon as Luis Perez shoots for his third major league victory when he takes the hill for the Jays. The lefty, who was up with the club last year for a few moments but didn't record a decision, has been primarily a relief pitcher in 2011 but is getting the start after posting his second win of the campaign on Tuesday when the team topped Seattle on the road by a score of 13-7.

In that matchup Perez, who has yet to earn a decision against Oakland in his brief career, allowed just a single win on three hits and a pair of walks, striking out three over the course of four innings of work, matching his longest outing of the season.

Over on the other side, the A's plan on putting Guillermo Moscoso on the mound to counter today. The right-hander, already with one win against the Jays this season, is in his third season in the majors but for the first two in Texas he saw little action.

Only up with the big club since late May this year, the 27-year old posted his second win in as many appearances earlier this week when he and the A's delivered an 8-4 win over the Baltimore Orioles at home. In that matchup Moscoso lasted six innings, permitting three runs -- two earned -- on five hits and a walk while fanning four.

Even though Willingham went over the wall for the A's last night, the team is still one of the weakest home-run hitting teams in the AL at this stage with just 81, third-fewest in the league. Of the team's 38 home runs at home thus far in 2011, Willingham has belted 12 of them, making him one of only two players on the squad to have more than four long balls in front of the hometown crowd.

In terms of the season series between the squads, the win yesterday pushed the Athletics ahead by a game, the team now leading by a count of 5-4. In the three previous seasons Toronto was the front-runner with 16 wins in 26 opportunities.