CINCINNATI (AP) — Though the plot changes a little, the outcome never does. No matter how things are going or who’s been slumping, the Houston Astros get to Cincinnati and win.

They’ve been doing it for three seasons.

Lance Berkman hit his 20th homer at Great American Ball Park, the most by any visiting player, and Hunter Pence hit a tiebreaking double in the ninth inning Monday night, leading the Astros to a 4-1 victory over the Reds.

Pence’s two-run double off Francisco Cordero (0-1) broke a 1-all tie and sent the Astros to their 10th straight win at Great American, a streak that started near the end of 2007 and is the longest such stretch in the majors.

Naturally, Berkman had a hand in it, hitting a solo homer in the sixth off Johnny Cueto. The opposite-field shot snapped his 0-for-16 slump and left him with more career homers (46) and RBIs (127) against Cincinnati than any other team.

Even when he can’t seem to get a hit, he’ll hit one here.

‘‘It’s kind of funny,’’ said Berkman, who is batting .174. ‘‘It seems that even when I’m struggling, I start feeling better and I look up at the schedule and we have a trip in here. It’s weird how that happens.’’

Weird? More like a certainty. Houston is 31-15-1 at Great American, which opened for the 2003 season.

The only surprise for the Astros was that Roy Oswalt couldn’t add to his 23-1 career mark against Cincinnati. The right-hander gave up only Joey Votto’s RBI single in seven innings, leaving with the game tied. Chris Sampson (2-0) got the last four outs, saving a bullpen that’s missing its closer indefinitely.

For the first time in his career, Oswalt has gone two straight starts without beating the Reds. He has two no-decisions against them this season despite pitching well.

‘‘I want to win, like everyone else,’’ said Oswalt, who allowed six hits. ‘‘I’m not pitching 20 years to go to the Hall of Fame. As long as the team wins, that’s what I’m here to do.’’

Oswalt escaped the Reds’ biggest threat in the sixth, when Cincinnati loaded the bases with two outs.

Reds’ boxscore

Astros 4, Reds 1

Houston Cincinnati

ab r h bi ab r h bi

KMatsu 2b 4 0 1 0 Tavers cf 4 0 0 0

Bourn cf 4 0 1 0 Dickrsn lf 2 0 1 0

Brkmn 1b 3 1 1 1 Nix lf 2 1 1 0

Ca.Lee lf 4 0 1 0 Votto 1b 4 0 2 1

JaSmth pr 0 1 0 0 Phillips 2b 4 0 1 0

Erstad lf 0 0 0 0 Bruce rf 3 0 0 0

Tejada ss 4 1 3 0 Encrnc 3b 4 0 0 0

Pence rf 4 1 2 2 RHrndz c 3 0 1 0

Blum 3b 3 0 0 1 AlGnzlz ss 4 0 2 0

IRdrgz c 4 0 0 0 Cueto p 2 0 0 0

Oswalt p 3 0 1 0 DMcDn ph 1 0 0 0

Byrdak p 0 0 0 0 Rhodes p 0 0 0 0

Sampsn p 1 0 0 0 Corder p 0 0 0 0

Totals 34 4 10 4 Totals 33 1 8 1

Houston 000 001 003 — 4

Cincinnati 000 001 000 — 1

E—Tejada (3), Bruce (1). DP—Houston 3, Cincinnati 1. LOB—Houston 5, Cincinnati 7. 2B—Bourn (3), Pence (3), Nix (4), Phillips (2), R.Hernandez (3). HR—Berkman (5). SF—Blum.

IP H R ER BB SO

Houston

Oswalt 7 6 1 1 2 2

Byrdak 2-3 1 0 0 0 0

Sampson W,2-0 1 1-3 1 0 0 0 1

Cincinnati

Cueto 7 7 1 1 1 5

Rhodes 1 0 0 0 0 0

Cordero L,0-1 1 3 3 2 0 2

Umpires—Home, Brian O’Nora; First, Fieldin Culbreth; Second, Kevin Causey; Third, Jim Wolf. T—2:33. A—12,365 (42,319).