Duda hit a pair of two-run homers only hours after the team gave him the starting job at first base, and New York beat the Cincinnati Reds 4-3 Friday behind Jenrry Mejia for its first victory of the season.
"I'm just glad to play and contribute any way I can," said the soft-spoken Duda. "It's just one day."
The 24-year-old Mejia (1-0), who beat out Daisuke Matsuzaka for the final spot in the rotation, struck out a career-high eight in six innings. Flashing a sharp breaking ball, he allowed one run and four hits in a steady rain and mist.
"It was a good game for us tonight. We needed it bad," Mets manager Terry Collins said. "We're a better team than we've played."
Bruce homered and drove in three runs for the Reds, who had won six straight at Citi Field. Mike Leake (0-1) gave up five hits and three walks in 6 2/3 innings.
"It was the Lucas Duda-Jay Bruce show, and Duda won," Leake said.
Mets left fielder Eric Young Jr. robbed Brandon Phillips of a home run, and backup catcher Anthony Recker threw out speedy pinch-runner Billy Hamilton trying to steal second for a big out in the eighth.
New York's maligned bullpen, which compiled a 10.61 ERA during Washington's three-game sweep to start the season, held on this time behind Valverde and fellow veteran Kyle Farnsworth, who got four outs.
The excitable Valverde worked the ninth for his first save with the Mets. He took over as closer when Bobby Parnell went on the disabled list with a partially torn ligament in his right elbow after blowing a save on opening day.
"I remember Valverde back in 2009 when he was throwing 99 mph," Bruce said. "He came right at me tonight. I just missed the one pitch and then he finished me off with the splitter. Pretty typical Valverde."
Mejia struck out five of his first eight batters and overcame five walks, which matched a career high. His right ankle was wrapped after the game -- Phillips' third-inning grounder hit him just above the outside part of his foot -- but he said he was fine.
Mejia pounded his glove and pointed to left field when Young robbed Phillips of a first-inning homer.
"I was just pumped up," Young said. "It ended up being the difference in the game because it was one run, so it was huge."
Bruce put Cincinnati ahead with an RBI single in the third.
Curtis Granderson beat the shift in the fourth when he grounded a leadoff double inside third base. Duda drove the next pitch into the Mets' bullpen in right-center for a 2-1 lead.
"Sometimes it's just about confidence," said Collins, who chose Duda at first over incumbent Ike Davis. "And maybe once in a while, when you feel good about yourself, you can start to do what everybody expects you to do."
David Wright opened the sixth with an infield single and, after Bruce robbed Granderson of extra bases with running catch in deep right-center, Duda ripped a line drive over the fence in right for his fifth career multihomer game.
Duda is 6 for 8 against Leake with three extra-base hits.
"He's a guy that sees me well. It didn't help that the two pitches he hit weren't quality pitches," Leake said.
Bruce cut it to 4-3 in the seventh with a two-run drive off reliever John Lannan.
Cincinnati rested Hamilton (0 for 12) and SS Zack Cozart (0 for 11). "For no other reason than trying to make sure that our other guys stay sharp," manager Bryan Price said. CF Roger Bernadina drew three walks in his first start for Cincinnati, and Ramon Santiago became the 24th Reds shortstop to play next to Phillips. ... It was the first stolen base attempt of the season for Hamilton, who set a professional baseball record in 2012 with 155 steals combined at Class A Bakersfield and Double-A Pensacola. The only other catcher to throw him out in 15 major league tries was Juan Centeno of the Mets on