Angels starter C.J. Wilson needs elbow surgery and is unlikely to pitch again this season. The news is a big blow to the playoff hopes of Los Angeles, which saw the competitor Astros and Blue Jays improve majorly at the deadline.

A bad week got worse for the Angels on Saturday with the news that lefty starter C.J. Wilson needs surgery to remove bone spurs from his pitching elbow and is unlikely to pitch again this season. The Angels had a one-game lead in the American League West on Monday, but then were swept by the Astros Tuesday through Thursday to fall into second place, failed to make an impact move at Friday’s trading deadline and, after receiving Wilson’s news Saturday morning, suffered their eighth loss in their last nine games and fell three games back in the division with Houston’s subsequent victory Saturday evening.

According to Wilson, whose 2008 season was ended by his having the same surgery in early August of that year and who had the surgery again after the 2012 season, he has had fluid drained from his elbow four times already this season and has been “pushing through” the pain caused by four bone spurs in his elbow for at least two months.

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“It’s just consistently getting worse,” Wilson told MLB.com’s Alden Gonzalez. “As it gets worse, the risk of blowing my shoulder out and being completely done with baseball increases, and I’m not willing to take that risk.”

Wilson was hit hard by the Astros in the Angels’ 10–5 loss in Houston on Tuesday, giving up six runs in four innings, three of them coming on home runs by Carlos Correa and Chris Carter in the first two innings of the game. However, in his five starts prior to that he had posted a 2.56 ERA, with the Angels going 4–1 in those games, and six of his last eight starts prior to Tuesday’s disaster had been quality.

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The Angels’ rotation as a whole has pitched well of late, but the team will clearly miss Wilson, as much of the recent success of the team’s other starters has been heavily dependent on the other eight men on the field. The Angels are fourth in the majors in park-adjusted defensive efficiency, and primary catcher Chris Iannetta, in stark contrast to previous seasons, has been among the better pitch-framers in the game this season, all of which has been crucial to the success of Hector Santiago, Garrett Richards and Saturday’s starter, rookie Andrew Heaney, this season.

Santiago made the All-Star team and leads the Angels with a 2.70 ERA on the season, but has done so with a .268 batting average on balls in play and a 4.02 fielding independent pitching figure, and has allowed nine runs (eight earned) in 10 innings over his last two starts. Since failing to make it out of the first inning against the Yankees on June 6, Richards has turned in seven quality starts in nine turns, posting a 2.67 ERA over that stretch, but has done so while striking out just six men per nine innings and benefiting from a .255 BABIP. Heaney has a 1.97 ERA through his first seven starts with the Angels, but with a below-average strikeout rate (6.7 K/9) and a .246 opponent’s average on balls in play. By comparison, Wilson had a .282 BABIP on the season, and that eight-start run prior to Tuesday’s bomb came with a league-average .296 BABIP.

Then there’s Matt Shoemaker. Shoemaker has been outstanding in his last two starts (13 IP, 5 H, 0 R, 4 BB, 17 K), but both have come on eight day’s rest. On the season, he has a 3.08 ERA in nine starts with six or more days of rest, but a 5.36 ERA in nine starts on a regular four day’s rest.

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None of that inspires much confidence in the Angels’ rotation going forward, and while Wilson’s departure synchs up nicely with Jered Weaver’s return from a hip injury, which should happen in the coming week, there’s little reason to have much confidence in Weaver either. Weaver was among my picks to go bust this season back in March and then pitched down to those expectations prior to missing six weeks with inflammation in his left hip.

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Weaver’s fastball averaged a career-low 85 mph prior to his injury, while his strikeout rate (4.6 K/9), home run rate (1.5 K/9), ERA (4.75) and FIP (4.78) were career worsts as well. Weaver had a strong run of five straight quality starts in May, but that came with a .243 BABIP and was followed by him going 0–4 with a 6.58 ERA in June despite a still-favorable .278 BABIP. That was a rough match for his results in six starts before that May run (0–4, 6.29 ERA, .303 BABIP). Weaver is very likely to be a significant downgrade from Wilson, but, much like CC Sabathia in New York, he’s a pitcher likely to be given an extremely long leash by his long-time manager based on his former ace status.

That’s bad news for the Angels, though the alternatives, again, aren’t terribly inspiring. Rookie Nick Tropeano has a 4.43 ERA in Triple A this season and gave up four runs in six innings in his spot start last Friday, while Drew Rucinski, who has replaced Wilson on the roster, was lit up in his only major league start in April and has a 5.03 ERA in 17 Triple A starts this season (albeit with a .336 BABIP).

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With Weaver having just made a rehab start on Thursday and Tropeano not on full rest until Monday, Wilson’s scheduled start on Sunday is being given to swing man Cory Rasmus, who has not pitched more than 2 1/3 innings or thrown more than 42 pitches in a game this season, the latter coming back on June 30. Rasmus was used as a fifth starter last September after Richards and Tyler Skaggs suffered season-ending injuries, but those were his first starts since 2011 and he was never stretched out beyond four innings or 64 pitches (though he did pitch well, posting a 2.37 ERA with a strikeout per inning, albeit with significant BABIP luck of his own). He had core-muscle surgery in March and did not start his 2015 season until June 19.

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Having failed to land the impact bat they needed at the deadline, the Angels appeared to be standing still while the Astros, who added Scott Kazmir and Carlos Gomez, raced by them this past week. With Wilson’s injury, the Halos have now taken a step backwards. As a result, in barely a week’s time the Angels have gone from first place in their division to worrying about holding on to a wild-card spot. After Saturday’s action, which saw Clayton Kershaw extend his scoreless streak to 37 innings against the Angels and the Twins and Orioles both win, the Angels are now closer to the third-place team in the wild-card race (Baltimore, two games back) than to first place in their division, and they’re equidistant between two big deadline winners, the first-place Astros (three games up on the Angels in the West) and the Toronto Blue Jays (three games behind them in the wild-card race).