Felix Doubront

After the Red Sox opened the A’s series with their worst loss since June 2000, the Sox turn to 24-year-old Felix Doubront to pull out them out of their nosedive by playing the stopper on the team’s four-game losing streak.

Doubront (10-6, 4.79 ERA) comes into Oakland after an underwhelming effort against the Royals in which he pitched five innings while giving up four runs, resulting in a no-decision in an eventual Red Sox victory. The start is largely indicative of Doubront’s season as a whole: rarely getting lit up, but also rarely dominating.

While acting as the Sox’s most consistent starter for much of the season’s early going, Doubront appears to have experienced a regression of sorts. After posting a 9-4 record with a 4.41 ERA in the first half of the season, Doubront has gone 1-2 with a 5.97 ERA in the second half, including an 8.16 ERA in August. While his ERA numbers never ballooned beyond those of Jon Lester or Josh Beckett, Doubront has been letting opponents on base as a high rate. The left-hander sports the worst WHIP among Sox starters (1.47) and leads the team in walks per nine innings (3.8). At the same time, Doubront is the leader among starters in strikeouts per nine innings with 8.9.

Doubront last faced the A’s on May 1 in one of his worst starts of the season, lasting just four innings (tied for a season worst) and giving up five earned runs (tied for his third most all season). Luckily for Doubront, the A’s lineup has seen drastic change over the last four months and retains just four players who faced him in that game, with none of them facing him more than twice.

Manager Bobby Valentine will likely be looking for Doubront to go deep into Saturday’s game after bringing out six relievers in Friday night’s 20-2 debacle. Longevity, however, has never been Doubront’s strong suit, particularly in 2012. In 23 starts this season, Doubront has pitched seven full innings just once and has not completed more than five innings or thrown over 100 pitches since July.

Starting opposite Doubront will be 24-year-old rookie A.J. Griffin, who is making his first start since coming off of the DL from a shoulder injury sustained in early August. The A’s right-hander made two starts in his rehab stint with Triple-A Sacramento, his most recent start ending with one run over five innings in a win for the River Cats.

Before going down with the injury during his start on Aug. 4, Griffin was on pace for an outstanding rookie campaign. After debuting in August, Griffin posted a 3-0 record with a 2.42 ERA in eight starts. In his first major seven major league starts (before leaving the game early in his eighth), Griffin went at least six innings and gave up no more than three runs.

Griffin faced the Red Sox earlier this season in his third career start on July 4, when he pitched six innings and gave up two runs, both of which were driven in by players not currently in the Sox lineup (David Ortiz and Adrian Gonzalez). On Saturday, Griffin will face a Boston lineup that has faced him a combined 13 times, resulting in two hits.

Red Sox vs. Griffin (RHP)

Mauro Gomez (3 plate appearances): .333 BA/.333 OBP/.667 SLG, 1 double

Ryan Kalish (3): .000/.000/.000

Jarrod Saltalamacchia (3): .333/.333/.333

Mike Aviles (2): .000/.000/.000, 1 strikeout

Cody Ross (2): .000/.000/.000, 1 strikeout

Athletics vs. Doubront (LHP)

Yoenis Cespedes (2 plate appearances): .500 BA/.500 OBP/.500 SLG, 1 RBI

Jonny Gomes (2): .000/.000/.000, 2 strikeouts

Cliff Pennington (2): .500/.500/1.000, 1 double, 1 RBI

Josh Reddick (2): .000/.500/.000, 1 walk