Bobby Jones (8-7) served up McGwire's 47th homer leading off the fourth inning, but by then had fired a four-run inning with a two-run double of his own. He allowed all three runs and eight hits with three walks and three strikeouts over seven innings to win for the first time since 2 July.
"I don't consider myself a hitter," said Jones, though he had seven hits in his last 19 at-bats entering the game. "I take a lot of pride in my hitting and moving runners over and getting bunts down."
Edgardo Alfonzo tied a career high with four hits and also drove in two runs for the Mets, who won for the fifth time in six games to move a half game ahead of the faltering Cubs in the race for the league's final play- off place.
McGwire had slipped into a tie for the major league lead when Sammy Sosa of the Cubs hit two homers on Monday night.
McGwire broke the National League record for homers before 1 September, which he and Sosa shared with Hack Wilson. Roger Maris, whose all-time record of 61 homers is being chased by McGwire, hit 51 before 1 September in 1961.
"It felt pretty good." McGwire said. "I've been off a millimetre, that's about it. I didn't see any breaking balls tonight, all I saw was fastballs and change-ups. He [Jones] is a very crafty pitcher: I got a couple of balls to hit and got a couple of hits."
Kent Mercker (8-9) was tagged for five runs and eight hits over five innings, walking one and striking out six.
In San Diego, Joey Hamilton allowed one run over seven-plus innings for a fifth straight win and Quilvio Veras and Steve Finley each drove in a run as the Padres defeated the Atlanta Braves 3-1 in the meeting between the two top teams in the NL.
Hamilton (10-9) improved to 5-0 in his last seven starts, limiting the Braves to six hits and a walk and two strikeouts before turning it over to his bullpen.
Trevor Hoffman struck out two in a perfect ninth for his major league- leading 39th save in 40 chances. San Diego are 154-0 when leading after eight innings since 24 July, 1996.
The Padres have won five of seven overall and are a league-best 43-13 at home. Atlanta had a four-game winning streak halted with their second loss in nine games.
In San Francisco, Jeff Kent's second homer of the game snapped a tie and the Giants beat the Chicago Cubs 8-7. Kent's first homer was a two- run blast off Kerry Wood that capped a five-run third inning.
Chicago fought back for a 6-5 lead in the sixth, but Barry Bonds levelled the game a half-inning later with an RBI single before Kent hit another two-run shot, off Terry Adams (7-7).
Bonds also drove in a pair of runs with a two-run triple in the third and has 24 RBI in his last 12 games.
One day after hitting two home runs to draw level with McGwire, Sosa was intentionally walked twice, once as the potential go-ahead run. McGwire has been walked 122 times this year, while Sosa has drawn 55 free passes.
In Cincinnati, Francisco Cordova fired a six-hitter for his second shut- out of the season as the Pittsburgh Pirates overwhelmed the Reds, 7-0. Cordova (10-10) scattered six singles while walking four and striking out six.
The Pirates had just eight hits but made the most of their scoring opportunities. They scored a pair of second-inning runs on groundouts and got homers from Jason Kendall and Kevin Young. Kendall hit a two-run shot and added a sacrifice fly and Young contributed his team-leading 22nd homer, a solo shot.Reuse content