On the day the A's traded starting pitcher Rich Harden and reliever Chad Gaudin to the Chicago Cubs, Duchscherer responded with the best outing of his career, facing only three batters over the minimum in a two-hitter as Oakland beat the Seattle Mariners 2-0 on Tuesday night.
"When I come to the field on my day to pitch I try to stay focused on the task at hand but it's tough," Duchscherer said. "We're like a family in here. I played with both of those guys for three-plus years, so it's tough. It's like your brother goes somewhere else and you don't get to hang out with him anymore but it's part of the business."
The A's and Cubs completed a six-player deal with Oakland receiving right-hander Sean Gallagher, outfielders Matt Murton and Eric Patterson and minor leaguer Josh Donaldson. Gallagher is expected to make his first start for the A's on Friday against the Los Angeles Angels.
Harden was Oakland's staff ace this season but that title now belongs to Duchscherer, the former reliever who was named to his second All-Star Game on Sunday.
Duchscherer allowed a two-out double to Richie Sexson in the fifth and a leadoff single to Miguel Cairo in the sixth. Sexson reached base on a two-base throwing error by Oakland catcher Kurt Suzuki in the third, though replays appeared to show the ball rolling foul off Sexson's bat.
"He was in complete control of the strike zone," Oakland manager Bob Geren said. "They have some pretty good hitters in that lineup over there so it was a great performance. Everything about it was efficient. He's always had innings and stretches of linking innings together where he was like that but he never really got in any trouble."
Duchscherer (10-5) retired the side in order six times including the ninth inning when he struck out Raul Ibanez to seal his first career complete game in a tidy 1 hour, 49 minutes, the A's quickest game this season.
Duchscherer struck out four and walked none, improving to 7-2 with a 1.34 ERA over his last nine starts. The win was his first in six decisions against the Mariners.
"He did a great job against us," Seattle manager Jim Riggleman said. "He showed why he's an All-Star. His breaking ball was the most effective, he threw it for strikes any time. We couldn't get to him."
Emil Brown had an RBI single in the first and Donnie Murphy added a sacrifice fly in the second for the A's who pulled within five games of the Angels in the AL West. The teams meet for a three-game series in Oakland this weekend.
Seattle starter Carlos Silva (4-11), who has won once since April 17, signed a $48 million contract with the Mariners in the offseason. He allowed seven hits and two runs in eight innings, striking out five.
"I was trying something different," Silva said. "I was positioning my arm differently, allowing my hands to stay loose and letting me relax. The adjustment allowed me to let the ball sink instead of trying to make it sink."
Ichiro Suzuki went 0-for-4 and remains 17 hits from 3,000 for his professional career. Ichiro, whose last 31 hits have all been singles, has not had an extra-base hit in 109 consecutive plate appearances, the longest such streak of his career.
Earlier Tuesday, the Mariners confirmed that left-hander Erik Bedard, slowed by tightness in his pitching shoulder, will not make his next start until after the All-Star break. Bedard was acquired in an offseason trade with Baltimore to be Seattle's staff ace but has been slowed by injuries and is only 6-4 in 15 starts this season.
Oakland DH Frank Thomas has been cleared to resume hitting but there is no timetable for when he will come off the DL. ... The last Oakland pitcher to throw a complete game shutout was RHP Joe Blanton, who beat Minnesota 1-0 on June 2, 2007.