By NICOLINO DIBENEDETTO
(AP) -- Struggles at the plate are leaving the Washington Nationals little margin for error on the mound.
That's been particularly evident during a recent stretch for the NL East leaders.
With the offense scuffling, Gio Gonzalez looks to continue his success on the road Tuesday night against the Colorado Rockies.
Washington (41-30) leads the division despite ranking near the bottom of the league in average (.238) and runs per game (3.71). That lack of production has put added pressure on a staff that's the best in baseball with a 2.97 ERA.
Overcoming those offensive shortcomings has become increasingly difficult for the Nationals, who have hit .200 and scored 25 runs while losing seven of 10. Their pitchers have compiled a 3.13 ERA during those games.
Even facing the lowly Rockies (28-44), who are last in the majors with a 5.29 ERA, couldn't inject some life into Washington's offense. Stephen Strasburg's six-start winning streak was snapped as the Nationals went 2 for 10 with runners in scoring position in a 4-2 loss Monday night.
Gonzalez (9-3, 2.55 ERA), among the league leaders with 101 strikeouts and a .182 opponents' average, hasn't needed much help on the road. The left-hander has won five of his last six starts away from home, posting a 1.98 ERA with 46 strikeouts in 36 1-3 innings.
He limited visiting Tampa Bay to two runs and seven hits over six innings of a 5-2 victory Thursday.
Gonzalez may need a similar performance in his first meeting with the Rockies since Bryce Harper continues to deal with a nagging back injury sustained in a loss to the New York Mets on June 7.
The 19-year-old is 4 for 23 with one RBI in his last seven games after going 0 for 4 with three strikeouts Monday.
"I've seen him with all kinds of contraptions (on his back), but I think right now it's for prevention," manager Davey Johnson told the team's official website.
After failing to mount much offense against Jeff Francis and his 8.56 ERA, the Nationals will try again when they face Christian Friedrich (4-4, 5.65).
The rookie left-hander is 0-3 with an 8.40 ERA in his last three starts, giving up six homers in 15 innings. Friedrich has struggled even more at home, going 1-2 with a 12.60 ERA.
Monday's win was only the fourth in 18 games for the Rockies, who had dropped six in a row at Coors Field.
"It is a good win, but only one win," Helton said. "We need to get a few more of these to get our season going."
Helton and Dexter Fowler have been bright spots lately for Colorado.
Helton has five hits over the last three games, and drove in the go-ahead run Monday with a sacrifice fly. Fowler is 9 for 20 over the last six contests.
Updated June 26, 2012