PITTSBURGH - The Montreal Expos have baseball's worst offense partly because they don't hit many homers or drive the ball to the outfield enough. For at least one night, though, the routine groundball provided more than enough scoring.

Terrmel Sledge drove in two runs with a grounder just past first base during a four-run seventh inning and the Expos halted Pittsburgh's 10-game home winning streak with a 6-2 victory Monday night.

The Expos got all the help they needed from an overconfident TV news reporter and an underachieving Pirates infield defense.

"I was watching TV at noon today and the anchorwoman said the Pirates had won 10 in a row at home and after tonight it would be 11," Expos manager Frank Robinson said. "I wish I could talk to her."

Pinch-hitter Ron Calloway, just up from Triple-A Edmonton after hitting .070 with Montreal earlier, added a two-run single in a go-ahead seventh in which the Expos hit the ball out of the infield only twice.

Ending the Pirates' longest home streak since they won 24 in a row late in the 1978 season, the Expos improved to 4-1 against Pittsburgh to win the season series for the third straight year.

Groundballs to first baseman Randall Simon proved Montreal's most reliable method of scoring after the Pirates' Craig Wilson hit a two-run homer in the first off Rocky Biddle. It is the Pirates' only multi-run homer in their 12 homers since July 2.

Biddle, who shut out the Pirates for five innings in a 4-0 victory on July 10, left after five Monday with the score tied at 2. Joe Horgan (3-0) retired the only batter he faced for the victory.

Montreal scored in the third on Brian Schneider's two-out RBI single, then tied it against Pirates starter Josh Fogg in the third when Brad Wilkerson doubled and came around to score on Jose Vidro's grounder to - of course - Simon.

Simon fielded the ball behind first but Fogg could not handle the first baseman's high throw, which arrived just before Fogg and second baseman Jose Castillo collided. Vidro was given a single and Fogg drew an error for not handling the throw, scoring Wilkerson.

"Josh should have caught it and stepped on first and he would have been out of the inning," Pirates manager Lloyd McClendon said with an audible sigh. "It just wasn't our night."