So the A's, looking to notch a series victory over the Rangers and move fewer than seven games back in the American League West on Thursday, felt rather confident in sending their young right-hander out to the mound for the rubber match.
But on a night when Oakland needed Mazzaro to dazzle the most, he struggled mightily. As a result, the A's eventually found themselves on the losing end of a 7-4 contest at the Ballpark in Arlington and 8 1/2 games back in the division.
Mazzaro endured his worst start of the year, surrendering a career-high-tying seven runs and 12 hits in the loss as he dropped to 6-3 on the season, a campaign that -- up until Thursday -- had treated him quite nicely, as evidenced by his recent string of four straight wins that brought a 2.12 ERA.
"He's been throwing the ball so well for us," said manager Bob Geren. "He'll bounce back after this. We've talked about it before, but these conditions, this lineup, always make it a little more tougher."
At the top of the lineup, Michael Young and Josh Hamilton combined for a 7-for-8 night and Vladimir Guerrero was responsible for three runs. The bottom half of the order wasn't too shabby, either. In fact, it proved to be rather hurtful in the form of monster homers from David Murphy and Taylor Teagarden in the sixth frame, the latter a two-run blast that not only ended Mazzaro's night, but Oakland's as well.
Before Teagarden's first jack of the season, the A's were down by just two runs. But another 2-2 pitch down the middle -- Mazzaro offered the same to Murphy -- changed it all.
"I really got ahead of some guys," the A's hurler said, "and I just couldn't put them away."
"These past couple tied games, they've been good baseball," Geren said. "Tonight, it was the sixth inning they got away. It was just a struggle. Those two homers put us out of range."
But Mazzaro was in trouble from the start, as he gave up two quick runs in the first before watching the pesky Rangers tack on another run in both the third and fifth frames.
"I didn't think we tried to do too much against Mazzaro," said Rangers manager Ron Washington. "We made him throw the ball over the plate, we swung at the pitches we wanted to swing at and everything worked out good."
The A's couldn't stage a large enough comeback in the ninth, when Coco Crisp hit a single with one out and eventually scored on a poke from Rajai Davis. Davis, though, ultimately got caught in a double play started by Kurt Suzuki that ended the frame and subsequently the game.
"We made an effort at the end," Geren said, "but it didn't happen. There's a lot of baseball left, obviously, with over 60 games to go. We just have to shake this one off."
Shaking a loss is one thing. Shaking a loss that leaves you at a good distance away from first place is another. But the A's aren't worried yet -- at least they didn't say so. The Rangers, meanwhile, are feeling a sense of comfort in their first-place seat.
"The key was to try and win each series we played, and we did," Washington said. "The guys have a knack of bouncing back. They don't get down. They came out tonight and did what they had to do: get out ahead and stay ahead. That's exactly what we did."
Texas got 5 2/3 innings from starter C.J. Wilson, who allowed three runs on seven hits with two walks and five strikeouts, improving to 10-5 on the year. He allowed a sacrifice fly to Suzuki in the first, but the A's didn't add on again until the sixth frame, when Kevin Kouzmanoff doubled and scored on a force-out from Landon Powell, who eventually crossed home plate on a Cliff Pennington double.
None of it could prevent a loss, just the club's fourth in its past 14 games. For Mazzaro, the seven runs matched the combined total of runs he allowed in each of his previous four starts.
"Some pitches he tried to get in, he left over the middle," Geren said. "His slider wasn't as devastating as we've seen, and his better ones were over the outside. Their big guys hurt us, and the ones down in the lineup just added on. Vin was getting ahead, but he just wasn't finishing them off."
Jane Lee is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.