ARLINGTON, Texas -- Boy, these Oakland Athletics sure are quick learners, aren't they?

Less than a week ago, Martin Perez baffled the A's hitters in a masterful three-hit, complete-game shutout. His devastating changeup and two-seam fastball kept the A's frustrated as they got quick outs and plenty of ground balls to waiting Rangers defenders. Perez needed 109 pitches to finish them off in nine innings, helping the Rangers to a sweep.

It was a completely different story Tuesday. Perez blamed himself, saying that he got too many balls up and that the A's took advantage. There's no doubt that's true. But while the A's were aggressive with Perez's fastballs up in the zone, they were disciplined with his changeup. They laid off the pitches diving out of the zone, working themselves into favorable counts. When Perez had to come back with his fastball, they were ready to pounce on it when he elevated it.

They didn't waste any time doing it, either. A Perez mistake -- a four-pitch walk with two outs to Yoenis Cespedes -- became a 2-0 lead when Derek Norris belted a double to left-center. Just like that, the Rangers were behind, just as they've been this entire series. Those runs ended Perez's scoreless innings streak at 26 and began another streak of three straight innings of at least one run allowed. Oakland scored one in the second and one in the third off Perez to take a 4-0 lead. They blew the game wide open in the fifth with five runs, four of those charged to Perez.

"He was living down there in the zone, and we weren't biting on it," Norris said. "He had to elevate to get the strikes. Maybe he was a little up in the zone today, but you know what? He threw the ball pretty well, I thought. When he got in a situation with runners on, we cashed some runs in. That's the way it works sometimes."

Perez's ERA rose by more than 1.5 runs and more than doubled. He can thank the opportunistic A's, who have put together a clinic so far in this series on working the pitcher and cashing in key chances. Yu Darvish threw 83 pitches and got through only 3 1/3 innings in Monday's loss. Perez threw 87 pitches and couldn't get out of the fifth.

"I need to work on my sinker a little bit more," Perez said. "They don't swing too much. They wait for a pitch and they know I'm missing the zone. That's what happened. I know I can be better."

In two days, the Rangers' top two pitchers have thrown a combined eight innings. It shouldn't be surprising the Rangers have lost those games fairly handily. Much of it is because of Oakland's fighter's mentality at the plate. The A's seem to know how to battle and when to go for the knockout punch.

"That's what Oakland does," catcher Robinson Chirinos said. "Even through the minor leagues, they take a lot of pitches, they make the pitcher work long in every AB and if you don't execute the pitch, they are in good hitting counts. That's what happened [Monday and Tuesday]."

After getting swept in Oakland last week by the Rangers, the A's have an opportunity to do the same to the Rangers in Texas. They've jumped out to 4-0 leads in both of the first two games and have done it against the club's top two pitchers. The A's aren't afraid to foul pitches off. They have terrific eyes at the plate and will lay off many pitches outside the zone, allowing them to get in good hitters' counts. It forces a pitcher to be on his game and Darvish and Perez weren't in the first two games of this series.

The A's gameplan is working. It's up to Rangers lefty Robbie Ross to see if he can change that.