For the remainder of the 2012 season, I’ll take a weekly look at one Angel’s recent performance and how it relates to their overall season and, in some cases, the fortunes of the team. This week, our focus lies on ace Jered Weaver.

On Monday, September 10, the Los Angeles Angels opened up a four-game set with their upstate rivals the Oakland A’s. Both teams were thriving, with the Halos taking 11 of their last 12 and Oakland 42-18 since the start of July. The Angels swept the A’s at the Coliseum the week before, helping them regain a hold in the choppy A.L. Wild Card race. Oakland could seal their 2012 fortunes with a series sweep.

Well, Oakland proved the winners of the week immediately, winning the first three games, including a 6-5 conquest that saw the Angels fail to score with runners at the corners in the bottom of the 9th and no outs. After solving the pitching problems that hampered their sluggish August, the Angels offense went to sleep as the A’s and their staff, 2nd in the AL in ERA, limited the Angels to 7 runs in the first 3 matches. When Jered Weaver took the mound on Thursday afternoon, his “Ace” status meant more than at any other point in the season. The Angels needed a win that could only be guaranteed by a brilliant start. Weaver gave it to them, allowing 2 hits and striking out 9 across 7 scoreless innings. He lowered his ERA to 2.74 and proved that despite recent health issues, he was prepared to lead the Angels to the edge of contention. The 5 of the 6 runs the offense came up with felt unnecessary with Weaver on the hill.

Since John Lackey’s departure to Boston and irrelevance following the 2009 season, Jered Weaver has pitched as the staff’s genuine #1. In 2010, he led the league in strikeouts and established a new career high in innings pitched (224) and ERA across a full season (3.01). Following his breakout campaign as a rookie in 2006, Weaver had been knocked around a bit, posting 2 seasons that failed to demonstrate efficiency or durability. 2009 got him over 200 innings for the first time, marking improvement despite peripherals in line with his 2007-2008 campaigns.

2010 today looks like a bit of an aberration. Weaver rode improved off-speed command to 233 strikeouts in 224 innings, a huge leap for someone who’d never reached even 8 K’s/9 before. Despite his impressive college pedigree, Weaver was seen as a middle of the rotation starter coming through the minors because he lacked a “woah” fastball.* He relied on above-average command and movement to succeed. His 3.06 FIP and career-high ground ball rate helped justify his overall improvements, but the strikeouts still baffled analysts. How could someone without heat or viscous breaking stuff  generate so many swing-and-miss pitches?

*I also remember questions about Weaver’s attitude. He once got tossed from a game for taunting the opposition by using bats as rabbit ears.

The answer was…Weaver couldn’t, at least not beyond 2010. His K-rate fell to 7.5/9 in 2011 and a rather dispiriting 6.8/9 this season. He’s completely reverted, and while his walk rate remains steady at a shade over 2/9, Weaver should be getting hit harder. He should see the increases in balls in play find their way past gloves, leading to base runners, runs, shorter outings, and a general drop in value. But…2011 was the best season of his career, featuring an ERA over half a run lower than 2010. His home run rate dropped from .92 to .76 and he averaged over 7 innings a start for the first time in his professional career. 2012’s comparable drop in value (167 innings in 26 starts, 2.74 ERA) still finds Weaver limiting the opposition to a WHIP of just over 1.

Is Jeff Spicoli Jered Weaver the byproduct of luck? A one-year look at Weaver in 2011 or 2012 would say yes, to an extent. His xFIP (a stat that predicts ERA based on league-average home run rates) has been far greater than his actual rate of run prevention over the last 2 seasons. In 2011, he posted a stellar 2.41 ERA against a merely good 3.80 xFIP. This season, the discrepancy runs from 2.74 to 4.05. The brief response says that Weaver is a capable starter who looks like an ace based on good fortune and an outstanding outfield. Weaver’s BABIP, typically low, sank to .250 in 2011 and .241 this season. Weaver’s allowed the lowest hit rate in the American League this season (7/9), a huge plus for someone who pitches to contact. Weaver’s walk totals should always impress, but limiting batted damage to the extent that he does helps mitigate his sagging K totals.

The strikeouts were a fluke, but Weaver’s ability to thrive while pitching to contact cannot be dismissed so easily. BABIP regresses to a mean quickly, sometimes in a week, usually by the end of a particular season. Weaver’s keeps falling. I wouldn’t penalize him for utilizing the heavy air in Anaheim to dominate in year’s past. Weaver’s career home ERA is over a full run lower than his road total, expected in a pitcher’s park but still marking an extreme discrepancy.

With the strange adaptation customary to Weaver, 2012 has been a little different. His fly ball rate, often approaching 50%, has sunk to a career-low 40%. His ground ball rate is a career high 37%. Even though the greatest percentage of fly balls are clearing the yard (Trout can’t rob everything), Weaver’s simply allowing less hard contact in the air. With Pujols anchoring 1st base with accustomed skill and Erick Aybar, Alberto Callaspo, and Howie Kendrick providing above-average glove work, Weaver’s supporting defense remains an advantage. Last year, he relied on Bourjos and Torii Hunter to provide ample range to track down fly balls. With Trout and Hunter a combined +41 in defensive runs saved this year, Weaver’s decreased fly ball rate could have to do with opponents changing their approaches. I know Weaver wouldn’t encourage hitters to avoid his outfield defense.

If Weaver’s ability to reinvent himself annually sounds dubious, consider: He throws 4 pitches at varying speeds for strikes. While his curveball and changeup have been used in similar fashions in 2011 and 2012, Weaver’s increased his fastball usage by 5%. Despite settling in the upper 80’s, Weaver’s fastball contains considerable movement and looks more dangerous when coupled with a 79-mph change or 71-mph curve he throws with identical arm angles. He can generate an increase in ground balls by relying on a moving fastball down in the zone whereas a high slider or change might generate fly balls. While Weaver would hardly attempt to change his game plan following 2011’s dominance, the accidental shift has still produced largely ideal results.

I say “largely ideal” because Weaver’s struggled during much of the 2nd half. After a 1.96 ERA in his first 15 starts, Weaver started serving up the Ervin Santana special. Five 1st half home runs demonstrated the best side of Weaver’s ground-ball tendencies, but the 12 bombs allowed since hastened questions regarding his health. His strikeout and walk rates have remained consistent, but so have Dan Haren’s. Even Weaver’s BABIP stayed below .300, suggesting that his hiccups can be almost solely attributed to the rise in home runs allowed. His Thursday start against Oakland was homerless.

Weaver made only two starts in June, slowed by a lower back injury. Shoulder tendinitis forced him to miss a start last week. The seven scoreless innings against Oakland represented both an easy victory for the Angels and a confident display of effectiveness moving forward. He’s proven near-impossible to predict, but a healthy Weaver seems to exceed expectations with impressive regularity. A tight race in the Wild Card could force manager Mike Scoscia to consider turning to Weaver on four days’ rest at season’s end. If clear of injury, Weaver should prove the decision wise.