Carpenter, who is 4-4 with a 5.08 earned-run average on the season, has not posted a victory since July 24 and has given up 12 runs over his last 18 innings.
That said, much of that damage was done by the Baltimore Orioles, who touched Capenter for seven runs in four innings in a 8-4 victory on Aug. 3.
Carpenter was much better in his most recent outing last Thursday.
The Toronto Blue Jays will hand the ball to Chris Carpenter on Tuesday in Oakland. (CP Photo)
The righthander held the American League West leading Seattle Mariners to three runs on eight hits over six frames in a frustrating 3-1 defeat.
Carpenter has pitched six innings or more in five of his last six starts. He has not faced the A's yet this season, but overall he owns a career mark of 1-2 with a 5.31 ERA against Oakland.
Oakland will counter Carpenter with Cy Young Award candidate Barry Zito.
Like Carpenter, Zito is looking to snap a losing skid.
After winning five straight the lefthander has suddenly lost back-to-back starts.
Zito last pitched on Aug. 8 and yielded four runs on seven hits during eight frames in a 4-2 loss to Boston.
Although it was his longest outing since July 1, Zito allowed more than three runs for the first time since June 27 -- a span of eight starts.
Zito also has the distinction of being the only A's pitcher to solve the Blue Jays this season.
Toronto has won six-of-seven meetings between these clubs this year. Oakland's one win came behind Zito.
On May 11, he limited Toronto to two runs on five hits during six innings in a 7-4 win. For his career, Zito is 2-1 with a 3.41 ERA against the Jays.
While the Jays have handled the A's this season, it hasn't always been the case. Oakland owns a 22-14 advantage in the series since the start of the 1999 campaign.
At home the A's are 9-3 against the Jays in the last three years.
Athletics will try to avoid losing three straight games for the first time since late July.
At 68-51, Oakland is 2 1/2 game behind the Anaheim Angels in the AL wildcard race and 4 1/2 games back of Seattle in the AL West.
The A's are 36-25 at home and 21-22 against the AL East this season, while Toronto is 12-19 against the West and just 24-32 on the road.
with files from Sports Network
