Braves 7, Athletics 2: Justin Upton and Evan Gattis hit second-inning homers as host Atlanta beat the team with baseball’s best record in the opener of a three-game series.

Atlanta won for only the fourth time in its past 16 games thanks to four homers, with Freddie Freeman adding a three-run shot in the third and rookie Phil Gosselin hitting his first major-league blast in the sixth. Alex Wood (9-9) gave up two runs on four hits in six innings as the Braves remained six games behind first-place Washington in the National League East and pulled within two games of the final NL wild-card spot.

The Braves knocked out Oakland starter Jason Hammel (9-10) after he allowed five runs on six hits in three-plus innings as the Athletics lost for the fifth time in six games. Nate Freiman hit a two-run homer and Derek Norris finished with two hits and a run scored as the Athletics’ AL West lead over the Angels was trimmed to one game.

Upton led off the second with his 22nd homer into the left-field seats and Gattis followed two hitters later with his 18th homer, a long drive deep over the fence in left-center. Jason Heyward and Gosselin singled with one out in the third and Freeman drilled his 17th homer to center to put the Braves ahead 5-0.

Norris doubled leading off the fourth and Freiman took a 3-1 Wood pitch out to left for his second homer, bringing the Athletics within 5-2. Gosselin, starting at shortstop because Andrelton Simmons missed the game with an abscessed tooth, hit a two-run shot to center and finished 2-for-4 with two runs scored.

GAME NOTEBOOK: Wood, David Carpenter, Jordan Walden and James Russell combined to retire the final 17 Oakland hitters. .. Hammel is now 1-5 with a 6.75 ERA in seven starts since being acquired by Oakland in a trade with the Chicago Cubs on July 5. … … Wood picked off Jonny Gomes at second base for the second out of the first inning -- the original safe call on the field overturned after a 1-minute, 30-second review following Atlanta manager Fredi Gonzalez’s challenge.