Angels’ Dan Haren and the art of the deal

Dan Haren anchored the Arizona Diamondbacks’ rotation for 21/2 years, going 37-26 with a 3.56 earned-run average from 2008 to July 2010, but the veteran right-hander can’t help but feel a little mystified about his desert stint.

“Arizona made the playoffs the year before I got there and the year after I left,” said Haren, who will pitch against his former club in Angel Stadium on Friday night. “And I was supposed to be the one who took them to the next level.”

Arizona’s struggles had more to do with pitcher Brandon Webb’s arm injury, an ineffective bullpen and a shortage of established run-producers than anything Haren did or didn’t do.

But the Angels also acquired Haren to bolster their playoff hopes and failed to make the postseason in 2010 and 2011, so the irony of the trade is impossible to ignore, and not just for Haren.

Jerry Dipoto was the Diamondbacks’ interim general manager who sent Haren to the Angels for left-hander Joe Saunders and minor league pitchers Tyler Skaggs, Patrick Corbin and Rafael Rodriguez in 2010.

And now Dipoto is the Angels’ GM, which will give him a unique perspective as he watches a player he traded away two years ago pitch for a team he currently runs.

“When you make trades, it’s not reflective of the fact you don’t like the player, it’s what’s smartest for the organization,” Dipoto said. “I loved Dan when he was with Oakland, I loved him in Arizona, and I think the world of him now.”

Though the Diamondbacks won the National League West without Haren in 2011 and the Angels haven’t reached the playoffs with the 31-year-old, Dipoto believes the deal helped both clubs.

Arizona, with baseball’s worst bullpen, little organizational pitching depth and a bloated $75.5-million payroll, was on its way to a 65-97 record and last-place finish in the summer of 2010, and Haren, who had 21/2 years and $32.5 million left on his contract, was Dipoto’s most valuable trade chip.

In the deal with former Angels GM Tony Reagins, Dipoto got a durable middle-of-the-rotation arm in Saunders, who went 12-13 with a 3.69 ERA and threw 212 innings in 2011, and two top prospects in Skaggs, who started the 2011 Futures Game, and Corbin, who was called up in late April and made five starts.

The payroll relief enabled the Diamondbacks to sign closer J.J. Putz to a two-year, $10-million deal before 2011. Combined with trades for setup men David Hernandez and Brad Ziegler, the bullpen went from awful to excellent.

Add breakout years from pitchers Ian Kennedy and Daniel Hudson and players such as Justin Upton and Miguel Montero, and Arizona nearly reversed its record, going 94-68 in 2011.

“We didn’t want it to be a five- or six-year rebuild, but we didn’t think it would happen in one year — that wasn’t planned,” Dipoto said. “We went from a club that was out of the running, operating at maximum payroll with a minor league system barren of pitching prospects, to a division winner with a pretty good stock of 25-and-under pitchers.

“Every team’s circumstances when making a trade are different. When that trade was made, it was the right thing to do for the Diamondbacks and the Angels.”

The Angels didn’t come away empty-handed. Haren has been a rotation rock for almost two years, going 5-4 with a 2.87 ERA in 14 starts in 2010, 16-10 with a 3.17 ERA in 2381/3 innings in 2011 and 4-6 with a 3.73 ERA in 13 starts this season.

Though his fastball velocity has dropped over the years from the 92-mph range to the 89-mph range, Haren has superb control of his cut fastball, split-finger fastball and breaking ball and has been baseball’s most durable pitcher, making a major league-high 250 starts since 2005.

“He’s a competitor, a professional, and he’s among the most refined command pitchers in baseball,” Dipoto said. “He can pitch to a lineup and to a game plan because he can throw the ball where he wants to. He controls the strike zone.”

What Haren can’t control is where he pitches. After reaching the big leagues with St. Louis, Haren, then 24, was traded with first baseman Daric Barton and pitcher Kiko Calero to Oakland for pitcher Mark Mulder in December 2004.

In December 2007, Haren was traded from Oakland to Arizona for outfielders Carlos Gonzalez and Aaron Cunningham, pitchers Brett Anderson, Dana Eveland and Greg Smith and infielder Chris Carter. In 2010, he was traded to the Angels for four pitchers.

Haren, in the final year of a four-year, $44.75-million contract that includes a $15.5-million option for 2013, believes the Angels have a World Series-contending team. He purchased a home in Orange County and hopes to raise his kids here.

“You could almost fill a big league roster with the guys I’ve been traded for,” Haren said. “For whatever reason, I haven’t stuck around longer than three years in one place. I hope that changes here.”

mike.digiovanna@latimes.com

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