When the Angels entered their four-game series against the Astros, they had only won three games in a row once this season and never had won four in a row.

But the Angels changed that with a four-game sweep of Houston, keyed by late lead changes, including a four-run rally in the eighth inning of a 9-5 win in the series finale on Sunday at Angel Stadium. It was their second-ever four-game sweep of the Astros, and their first since 2014; it was their first four-game sweep of any club since doing it against the Mariners from Aug. 10-13, 2017.

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After an incredibly slow start to the season that saw the Angels serve as sellers at Monday's Trade Deadline, they've been playing much better recently. They improved to 8-3 over their last 11 games, but at 17-25, they are still five games behind second-place Houston with 18 games remaining. But Angels manager Joe Maddon believes this club isn’t out of it yet.

“I've been involved in some really dire-looking situations,” Maddon said. “This week is pretty pertinent, but the most important game of the year is going to be Tuesday. And then the most important game of the year is going to be Wednesday. We have to reduce it to one day at a time. All the time, but it's true. If we're able to do that, you can see something good happening.”

Rookie right fielder Jo Adell sparked the winning rally with a leadoff hit off Astros lefty Framber Valdez, a hard-hit single that had an exit velocity of 108 mph, per Statcast. Max Stassi, activated prior to the game, followed with a single to center and Jared Walsh plated the go-ahead run with a chopper to right field to score Adell. The Angels loaded the bases with nobody out and Luis Rengifo, who entered the game in place of an injured Franklin Barreto, walked to bring home a run before Justin Upton ripped a two-run single with one out to give the Angels a four-run cushion.

The Angels have seen better starting pitching and timely hitting during this stretch, which were both huge issues early in the season. Right-hander Jaime Barria scuffled early, giving up a two-run homer to Kyle Tucker in the first and a solo homer to Aledmys Díaz in the second, but recovered to get through five innings. Angels starters have combined to post a much more respectable 2.95 ERA over their last 10 games.

"I think the first inning I couldn't really focus; it was really hot," Barria said through an interpreter. "But from there, I tried to amp myself up and be more aggressive with all my pitches, just going out there to get outs. I just wanted to try to get through five innings because our bullpen has been used a lot."

Upton, who provided a key hit in the eighth, has also started to heat up, while Anthony Rendon is regaining his power stroke, hitting a go-ahead three-run homer in the final inning of Game 2 of Saturday’s doubleheader and a game-tying two-run homer in the third on Sunday. The offense scored a combined 32 runs in the series.

“Our offense, we’re hitting our stride, and it’s been fun to watch since I got back here,” said right fielder Taylor Ward, who was 2-for-3 with two RBIs. “And our pitching staff has done well so far, gotta keep doing what they’re doing. We’re a good ballclub.”

The defense has also been better, with several highlight-reel plays over the last week, including yet another one from Andrelton Simmons on Sunday. Simmons ran back 80 feet to make an over-the-shoulder grab to rob Jack Mayfield of a hit in the fifth inning.

“He's so good on pop-ups, he just is,” Maddon said. “And it was tough because he knew J-Up was coming. So he caught it and did, like, the pop-up slide. This is coming off an ankle [injury], too, so there's all kinds of stuff going on. He's just a really good baseball player. He's the kind of guy that every manager would appreciate.”

The main issue has now become the bullpen, which Maddon admitted needs to start to take shape and hold leads better. The Angels lead the Majors with 12 blown saves, including another one on Sunday, with Felix Peña allowing two runs to tie the game in the seventh.

“If we could define the bullpen, and we get to know what to expect there, that's a big part of it, too,” Maddon said. “I think overall, the starting pitching continues to get a little bit better with each time out. And you got to win games like this to really earn the right to move to the next level.”