"Unable to an add an impact bat, the Angels chose to upgrade their rotation Sunday when they acquired ace right-hander Dan Haren from the Arizona Diamondbacks for left-hander Joe Saunders, minor league pitchers Patrick Corbin and Rafael Rodriguez and a player to be named.

"We didn't see a fit from an offensive standpoint we thought would make us better," General Manager Tony Reagins said before the Angels' series finale against the Texas Rangers.

"There are still opportunities out there, and we will be aggressive in pursuing them. We're just looking for opportunities to improve the club. We didn't say it had to be an impact bat."

Saunders, who threw a gem in his last start for the Angels, allowing one run and seven hits in seven innings of a 1-0 loss to Texas Friday night, was shocked when Manager Mike Scioscia pulled him off the field during the team's pregame stretch to inform him of the trade.

"I had no idea," Saunders said in the clubhouse, fighting back tears. "Scioscia came out and got me, and I thought he was going to tell me I was [making my next start] on three days' rest. Then I saw Tony in the office ? it's hard.

"It's part of the game, it's a business, but it's tough leaving the guys. That's the hardest thing, because they're my family. I spent eight years with these guys. It's tough."

Haren, 29, has won 30 games over the past two seasons, trailing only two-time Cy Young Award winner Tim Lincecum, and the three-time All-Star, who could make his Angels debut against the Boston Red Sox Monday night in Anaheim, has averaged 15 wins a year over the past five seasons.

The 6-foot-5, 215-pounder, who mixes a split-fingered fastball with his fastball and breaking ball, is 7-8 with a 4.60 earned run average this season, and his 141 strikeouts is tied for the National League lead.

The Angels gave up a lot to get Haren — Saunders is one of baseball's better young left-handers, going 33-14 in 2008 and 2009 and 6-10 with a 4.62 ERA this season, and Corbin, a lefty who was a second-round pick in 2009, went 8-0 with a 3.86 ERA in nine starts at Class-A Cedar Rapids before being promoted to Class-A Rancho Cucamonga, where he is 5-3 with a 3.88 ERA in 11 starts.

But in Haren, they acquired a front-of-the rotation starter who will be under club control through 2013. Haren is in the second year of a four-year, $44.75-million contract that pays him $8.25 million this season, $12.75 million in 2011 and 2012 and includes a $15.5-million club option for 2013.

The addition of Haren and loss of Saunders, who makes $3.7 million this season, will add a net of about $1.8 million to the Angels' $121-million payroll."