© 2014 MLB Advanced Media, L.P. All rights reserved.

5/3/2014 2:15 P.M. ET

Cespedes making better adjustments at plate

BOSTON -- Yoenis Cespedes may not be back to 100 percent yet, after suffering a strained left hamstring last week. But his swing is looking mighty healthy.

Oakland's outfielder, who got the start at designated hitter on Saturday in Boston, entered the day with four hits in six at-bats since returning from the injury.

"He feels good with his mechanics, right now," said manager Bob Melvin. "Even with the days off, he was still working in the cage. One of the things I think goes unnoticed with him is how hard of a worker he is. He sometimes overdoes it, as far as his work in the cage. His swings have been great."

Red Sox righty Clay Buchholz threw a 2-1 cutter that Cespedes swung through on Friday night. Buchholz came back with two straight fastballs, both of which Cespedes fouled off, before challenging him with the same cutter the outfielder had just missed badly on.

Cespedes drove the ball in the gap for a double, his third in his last two games.

"That's the type of things we saw him do in 2012, too, when he didn't know the league as well and he had to make adjustments from at-bat to at-bat and, really, in the middle of at-bats," said Melvin. "That's what he did yesterday, and it seems he's making those adjustments better again."

Abad off to a stellar start in 2014

BOSTON -- In an A's bullpen that's allowed 11 earned runs over the last five games heading into Saturday, Fernando Abad remains untouchable.

Oakland's lefty hasn't given up a run over his first 12 outings, spanning 11 2/3 innings, and has struck out 14 of the 41 batters he's faced.

His 12th trip to the mound was maybe the biggest to date -- and perhaps the most fun to watch. Even Abad smiled and said, "Yeah, that was a good one."

David Ortiz was the batter in a one-run game with one out and runners at second and third in the fifth inning on Friday. Abad fell behind, 2-0, on back-to-back sliders, then fought his way back into the count with four straight fastballs. At 3-2, Abad went back to his slider, and this time didn't miss, freezing Ortiz with a perfect pitch for a called third strike.

Abad was then ordered to intentionally walk Mike Napoli to get to Grady Sizemore, who went down swinging to end the frame.

"I don't know, at the time, what a bigger role in the game was than that," said manager Bob Melvin. "We're down, 2-1, and have runners on base. He comes in, and if it gets away from us there, then the game goes in a different direction.

"His outs are prominent to begin with, maybe not the clean-inning type of thing in the eighth, at this point. But we're using him with guys on base when we need to get a big out against the lefty, and he's been very successful with that."

Left-handers are hitless with eight strikeouts in 14 at-bats this year against Abad, who has handled righties just fine, too. They're 2-for-23 (.087) off the confident lefty, who could begin seeing more complete innings because of his continued success against hitters from both sides of the plate.

"He is fearless when he's out there, very confident in his stuff -- and it shows," said Melvin. "And there's something to that. If you're seeing it, the hitter's seeing it, too. There are some guys out there that have some trepidation, and I think hitters sense that, too. Other guys are very confident when they go out there, no matter what the situation is, and he exudes that."

Worth noting

• The A's have yet to announce a starter for the second game of Wednesday's scheduled doubleheader against the Mariners at the O.co Coliseum and are unlikely to do so until returning home on Monday.

They're expected to choose between Triple-A Sacramento pitchers Josh Lindblom and Arnold Leon for the assignment.

Jane Lee is a reporter for MLB.com. Read her blog, Major Lee-ague, and follow her on Twitter @JaneMLB. This story was not subject to the approval of Major League Baseball or its clubs.