OAKLAND, Calif. (AP) -- Some of Gio Gonzalez's best memories are from his days pitching at the Oakland Coliseum.
It might not be such a special place for the Washington left-hander anymore.
Facing his former club for the first time since being traded away following the 2011 season, Gonzalez had a nightmarish afternoon after giving up a pair of three-run home runs to former Nationals' farmhand Derek Norris in a 9-1 loss to the Oakland Athletics on Sunday.
"It's always nice to come back to Oakland and see some familiar faces and enjoy it, but I still got a job to do," Gonzalez said. "Obviously, it was a different story today."
It was a rough return to the Coliseum for Gonzalez, who pitched for the A's for four years and was making his first start against his former club.
Washington's left-hander labored through 4 1-3 innings and gave up seven runs and nine hits. He struck out four and walked three in his worst outing in Oakland since giving up 11 earned runs to Minnesota on July 20, 2009.
Gonzalez (3-3) was also caught on television yelling at a teammate in Washington's dugout after the second. Earlier in the inning, the Nationals allowed a high pop-up by Yoenis Cespedes to fall to the turf and roll foul. Cespedes eventually walked before the next batter, Norris, hit his second two-out home run of the day.
"Nothing happened," Gonzalez said when asked about what happened in the dugout.
Both of Norris' home runs came on identical two-out, 3-0 pitches from Gonzalez. Norris, who spent five seasons in Washington's minor leagues, was also part of the trade that sent Gonzalez to the Nationals.
It's the first multi-homer game of Norris' career. The six RBIs are tied for the most by an Athletics catcher since 1914.
"Everyone knows (Gonzalez) has good stuff and you have to get on him early," Norris said. "It just happened to work out a little bit better than it initially was planned out to be, not once but twice."
Before the game, Washington placed first baseman Adam LaRoche on the disabled list with a right quad strain. LaRoche, who has five home runs and 21 RBIs, joins Nationals third baseman Ryan Zimmerman and outfielder Bryce Harper on the DL.
Without its top three hitters, Washington did little offensively.
Oakland starter Scott Kazmir retired the side in order five times in the first six innings, and the Nationals were on the verge of being shut out for the second time in three days until Zach Walters' RBI single off Jim Johnson with two outs in the ninth.
"We got manhandled today," Washington manager Matt Williams said. "(Gonzalez) didn't have a breaking ball early and missed with his fastball and they made him pay for it. That was the story of today."
The A's completed their majors-leading fourth series sweep with another blowout of the Nationals. Oakland, which shut out Washington in the series opener, outscored Washington 21-4.
Nick Punto added two hits and three RBIs while Brandon Moss singled twice and doubled for Oakland.
Kazmir (5-1) bounced back from his first loss of the year to pitch seven scoreless innings while allowing only four hits. He struck out four and didn't walk a batter for the fourth time this season.
In the lineup because of a left-hander on the mound, Norris blasted a 3-0 pitch from Gonzalez over the wall in left with two outs in the first.
Oakland led 4-0 when Norris came up in the second, again with two runners on. Gonzalez ran the count to 3-0 before Norris hammered the ball down the left field line for his fourth home run this season.
Punto added an RBI single in the first and a two-run double in the seventh.
NOTES: Gonzalez has a 10.13 ERA in the first inning of games this season compared to a 2.72 mark in all the other innings combined. ... The Nationals swept a three-game series from Oakland at home in 2005, the only other time the two teams have faced one another. ... Washington called up 1B Tyler Moore from Triple-A Syracuse to replace LaRoche. Moore batted seventh and went 0 for 3. ... RHP Jordan Zimmerman (2-1) carries a 2.92 ERA into his start Monday at Arizona.
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