They wouldn't mind more offensive outbursts like the one they got in their series opener with the New York Yankees, either.
Haren looks to build on one of the best starts of his career and help the surging Angels extend their season-best winning streak to eight games Tuesday night against Andy Pettitte and the Yankees.
Weaver's first appearance in Anaheim since throwing a no-hitter there May 2 against Minnesota was a short one, as he exited Monday's game after making just 12 pitches. The Angels (25-25) announced that Weaver, 6-1 with a 2.61 ERA, has a lower back injury and will have an MRI on Tuesday.
Any extended absence for Weaver could be disastrous for Los Angeles, but if its offense can replicate its production from Monday, the team should be just fine.
The Angels matched their season highs in runs and hits (15) as Mark Trumbo led off the ninth inning with a homer to seal a 9-8 victory, the team's seventh in a row. Trumbo also doubled and tripled while Howie Kendrick and Kendrys Morales drove in three runs apiece for Los Angeles, which got back to .500 for the first time since April 9 and snapped the Yankees' season-best five-game winning streak.
"Hopefully it's a breakout game," manager Mike Scioscia said. "During the streak, we have not been swinging the bat well. We've been doing just enough to win, so hopefully this will get us to a different place."
The Angels, who are in the midst of their longest winning streak since reeling off eight in a row in July 2009, are 22-4 when scoring at least four runs but 3-21 when plating three or fewer.
Haren (2-5, 3.76 ERA) has been the unlucky recipient of many of those low-scoring games - his 2.23 run support average is the fourth-lowest in the majors - but one run was all he needed against Seattle on Thursday.
The right-hander tossed a four-hitter while striking out a career-high 14 in a 3-0 win. The three-time All-Star, who struggled with a sore back for the early part of the season, had posted a 5.79 ERA in losing his first four May starts.
Haren went 1-0 with a 2.30 ERA in two starts against the Yankees (26-22) last season, including a four-hit shutout in September, and he's 5-1 with a 3.43 ERA in 10 career outings versus New York. He held Mark Teixeira without a hit in six at-bats last year, but he'll have to be careful pitching to the first baseman Tuesday.
Teixeira homered, singled and walked three times Monday, and is 11 for 21 with four home runs, three doubles and 10 RBIs for a 1.868 OPS in his last six games.
While Teixeira has been locked in at the plate, Pettitte (2-1, 2.53) has put together a couple of performances reminiscent of his prime in winning his last two outings. The 39-year-old left-hander allowed four hits in eight innings in a 4-0 victory over Cincinnati on May 18 and followed that up by permitting two runs and seven hits in seven innings in Wednesday's 8-3 win over Kansas City.
"I feel like I'm moving the ball around the zone and that makes it difficult to hit," said Pettitte, who has totaled 17 strikeouts and two walks in his last two outings.
Pettitte displayed similar dominance in winning his two starts against the Angels in 2010, posting a 0.64 ERA while striking out 14 and walking three over 14 innings. He was 0-4 with a 7.91 ERA in his previous six regular-season starts in the series.