ARLINGTON, Texas (AP) _ Tim Wakefield's knuckleball kept dancing and his Boston Red Sox teammates supplied him with more than enough support.

Bill Haselman's first career grand slam broke a 1-1 tie in the sixth inning to back Wakefield's six-hit pitching and the Red Sox went on to hand the fading Texas Rangers their 12th loss in 13 games, 7-1 Saturday night.

``Tonight we had a combination that can't be beat with Wakefield on the mound and seven runs on the scoreboard,'' Red Sox designated hitter Jose Canseco said.

Wakefield (11-1) won his seventh straight in his fifth complete game. He struck out seven and walked three while lowering his ERA to a major league best 1.58.

``It's always more comfortable to pitch with a nice lead,'' Wakefield said. ``I always have confidence that our lineup is going to put runs up on the board. And my job is to hold the other team down.''

Boston has scored four or more runs in each of Wakefield's last seven starts.

The Red Sox won their fifth straight on the road and improved to 24-15 away from Fenway Park. They lead the AL East by 5 1/2 games over Baltimore and New York.

For the Rangers, the slide continues. Since July 17, Texas has fallen from one game out to 10 games behind the California Angels in the AL West.

``We're just not doing the things that are required to win ball games,'' Rangers manager Johnny Oates said. ``In 28 years of baseball, I've never been in the situation we're in right now. We're not hitting and we're not making the pitches, but it's not for a lack of effort.''

Canseco added his 10th homer, a two-run blast in the seventh off reliever Dennis Cook, for a 7-1 lead. Canseco went 3-for-5 with three RBIs against his former team.

Haselman, who entered the game in the second inning in place of injured catcher Mike Macfarlane, made the Rangers pay after Texas starter Kevin Gross (4-10) walked John Valentin intentionally to load the bases in the sixth.

Haselman blasted a 1-2 pitch over the fence in center field for his second homer of the season.

``To hit your first grand slam feels great,'' said Haselman, once a Rangers minor leaguer. ``It was especially great in that situation, in a tie game.''

Canseco led off the sixth with a single, went to third on Tim Naehring's double, then Valentin got the intentional pass to load the bases.

Boston took a 1-0 lead in the first when Lee Tinsley led off with a single, moved to second and third on grounders, and scored on Canseco's single.

Texas tied it 1-1 in the fifth on Otis Nixon's RBI single.

Gross, who started the night with a 7.00 ERA, allowed five runs and six hits in six innings.

Notes: Macfarlane had a rough night. He was charged with three passed balls in the first 1 2-3 innings before he was replaced by Haselman. Macfarlane was hit by a pitch in the first inning and suffered a bruised nerve behind his left elbow...Haselman also had a passed ball in the third but the Rangers were unable to take advantage. ...Canseco hit his 19th career homer at The Ballpark in Arlington...The crowd of 46,717 was the largest ever for a regular-season game at The Ballpark...Texas hasn't won at home since July 9, a six-game streak.