That would be Boston, which tries for a sweep of Oakland this afternoon in the finale of a three-game series at Fenway Park.
After stumbling to an 11-12 record in April, the Red Sox rebounded in May with an 18-11 mark, winning 10 of their final 13 games that month. Boston has extended that run in June, winning the first two contests of this series to put itself into position for its first sweep of Oakland since winning all three home meetings from Aug. 1-3, 2008.
These teams split 10 meetings a year ago, with the Red Sox winning four of the seven bouts held at Fenway.
The Athletics, meanwhile, countered a 12-12 April with a 16-12 May, but they have lost three of their last four games to fall to 5-4 on their current 10- game road trip.
Oakland has blown two early leads in this series, yielding a 4-0 advantage after five innings on Tuesday en route to a 9-4 setback. The A's then jumped out to a 3-0 lead in the first inning of Wednesday's contest, helped by Kurt Suzuki's two-run homer, but the Red Sox countered with two runs of their own in the bottom of the frame on a two-run double by Kevin Youkilis before going ahead for good on David Ortiz's two-run homer in the fifth. That helped guide Boston to a 6-4 triumph.
Ortiz, named American League Player of the Month of May earlier in the day, went 2-for-2 with a pair of walks and is hitting .360 with 11 homers and 29 RBI in 25 games in May and June following an April in which he batted only .143 with one homer and four RBI.
Daisuke Matsuzaka battled through 6 2/3 innings to take the win, allowing only the three first-inning runs.
"It's like he kicked it in gear. His first pitch strikes were tremendous," Red Sox manager Terry Francona said.
Ben Sheets appeared on his way to a solid outing, but instead took his fourth loss of the season thanks to Ortiz's homer. He was charged with four runs on seven hits over six innings.
"I really wanted him to make something happen," Sheets said of facing Ortiz. "I didn't really want to put him on base. I thought I had a good opportunity, but looking back I threw the same pitch back-to-back in the same location. He's a good hitter and he got to it."
Wednesday's setback was costly, as it dropped Oakland a game back of Texas for first place in the AL West.
Oakland was relieved to have Brett Anderson back in the rotation last Saturday and hope that the left-hander can turn in another solid outing again today.
Pitching for the first time since April 24 due to a strained left forearm and elbow tendinitis, Anderson held the Tigers to just three hits over 5 2/3 scoreless innings without a walk and four strikeouts. The victory improved him to 2-1 on the season with a 1.88 earned run average in five starts, as Anderson has allowed just six earned runs over 28 2/3 innings with four walks and 21 strikeouts.
"My stuff was pretty sharp, which I was pleasantly surprised with," Anderson said.
The 22-year-old hasn't allowed a run in two road starts, going 1-0 while pitching a total of 11 2/3 innings. In three career starts against Boston, Anderson is 2-1 with a 2.05 ERA.
Ortiz is seeking his first career hit versus Anderson, as he is 0-for-7 lifetime against the hurler.
Wakefield was drilled for nine runs on 12 hits and three walks over just 3 2/3 innings, falling to 1-3 with a 5.68 ERA.
The 43-year-old has faced Oakland 39 times in his career, 28 of those starts, and is 11-6 with a 4.08 ERA.