Houston @ Pittsburgh preview

Last Meeting ( Jul 4, 2011 ) Houston 3, Pittsburgh 5

THE STORY: The Pittsburgh Pirates haven't been this close to first place in the National League Central this late in the season since 1997, when they trailed the Houston Astros by 1 1/2 games on July 21. They enter Tuesday's home meeting with the Astros 1 1/2 games behind St. Louis thanks to a run of nine wins in 13 games. Houston, which owns the worst record in the majors, has lost four straight contests and nine of its last 10.

TV: 7:05 p.m. ET, FSN (Houston), Root Sports (Pittsburgh)

PITCHING MATCHUP: Astros LH Wandy Rodriguez (6-4, 2.97 ERA) vs. Pirates RH Jeff Karstens (6-4, 2.65 ERA).

Rodriguez tossed seven scoreless innings against Texas on Thursday, marking the fourth time in six outings he did not give up a run. The 32-year-old has gone 5-1 with a 1.77 ERA over his last nine outings. Rodriguez is 7-4 lifetime against Pittsburgh and enters with a four-game winning streak vs. the Pirates.

Karstens went 3-0 in six June starts, allowing three earned runs or less and working at least 6 2/3 innings in each outing. He yielded two runs over seven frames in a win at Toronto on Thursday, the 10th time in 11 starts he gave up fewer than three earned runs. Karstens is 2-2 in six career meetings with the Astros, including a triumph at Houston on June 14 in which he tossed 6 2/3 scoreless innings.

ABOUT THE PIRATES (44-41): Pittsburgh is on the verge of posting its first winning record at the All-Star break since going 49-39 in 1992. All-Star closer Joel Hanrahan is one save away from the club record for most at the break. He notched his 25th on Monday to tie Mike Williams, who hit the mark in both 2002 and 2003. 3B Josh Harrison left Monday's game after three innings due to dizziness. Harrison was involved in a collision at home plate with Houston catcher Carlos Corporan, which likely caused the problem.

ABOUT THE ASTROS (29-57): All-Star RF Hunter Pence went 2-for-3 in Monday's loss, extending his hitting streak to nine games. Pence hit his 24th double and the Astros' major league-leading 177th of the season. Houston leads Boston in that category by two. The Astros have dropped seven of their last eight road games. 1B Carlos Lee drove in a pair of runs Monday, giving him 10 RBIs in his last nine contests.

FINAL PITCH: The Pirates recorded their fourth consecutive sellout Monday, marking the first time they have reached capacity for four straight games at PNC Park since the stadium opened in 2001.