ST. PETERSBURG, Fla. -- Isaac Paredes hit a grand slam during Tampa Bay's six-run second inning, and the Rays beat the Oakland Athletics 9-5 on Friday night to extend their season-opening win streak to seven games.

The Rays have now won each of their first seven games by four or more runs, the longest such streak in American and National League history, according to ESPN's Stats & Information. The Rays are also the fifth team since 2000 to start a season 7-0.

Harold Ramírez, Manuel Margot, Christian Bethancourt and Wander Franco also homered for Tampa Bay. The Rays' 18 homers are the most through seven games in team history.

"Can we keep it up?" Rays manager Kevin Cash said with a laugh. "I think we've got to be very pleased with everybody in the lineup is contributing."

Tampa Bay's Zach Eflin (2-0), who signed a $40 million, three-year contract in the offseason, gave up three runs over six innings. The deal was the largest free agent agreement in franchise history.

"What an awesome game, getting that huge six-run inning," Eflin said. "Kind of let me coast a little bit. Just a great night."

Eflin stayed in the game after Ramon Laureano's infield single in the sixth went off his foot. The right-hander started a nifty inning-ending 1-6-3 double play on the next pitch to Jace Peterson.

Oakland got solo homers from Ryan Noda and Shea Langeliers. The Athletics have lost five of seven.

Ramírez had a leadoff homer and Paredes went deep off Ken Waldichuk (0-2) in the second as the Rays went up 6-1. Waldichuk walked three in the inning but recorded consecutive strikeouts before Paredes connected on his second career slam.

Tampa Bay opened an 8-2 lead on third-inning homers by Margot and Bethancourt.

The Rays have outscored their opponents 53-17 this season. With five home runs on Friday, the Rays are the sixth team in major league history with 18 home runs in their first seven games of the season.