J.J.Hardy of the Orioles reacts after being called out on strikes in the fifth inning. The Orioles have nine hits in two games against the Astros, the team with the worst record in baseball. (GAIL BURTON/AP)

In a month when the Baltimore Orioles made three trades to bolster their pitching, the club’s offense ended July with a whisper not befitting of a playoff contender.

The Orioles were shut out for the second time in the past three games Wednesday night, this one an 11-0 loss to the Houston Astros, who have the worst record in baseball.

A day after recording three hits against the Astros, the Orioles managed six.

Houston left-hander Brett Oberholtzer (1-0), making his first major league start and just his fourth appearance in the big leagues, tossed seven scoreless innings. Oberholtzer, who was thrust into a starting role earlier in the day when left-hander Erik Bedard was scratched, made easy work of the Orioles.

Meantime, Orioles right-hander Miguel Gonzalez (8-5) suffered the worst outing of his career, lasting just 32 / 3 innings.

If the Orioles (59-49) are going to be serious playoff contenders, they must play better against lesser competition. Wednesday’s loss dropped their record to 22-21 against teams below .500. Their series against the Astros begins a string of 14 games out of 17 against teams with losing records.

The Orioles’ 11-run loss on Wednesday was their worst shutout loss in nearly two years, since dropping a 13-0 decision to the Toronto Blue Jays on Aug. 31, 2011. It was also their largest margin of defeat since losing 19-7 in Minnesota on July 16, 2012.

The team has dropped six of its past eight games.

Earlier in the day, the Orioles acquired right-handed starter Bud Norris from the Astros for outfielder L.J. Hoes, pitching prospect Josh Hader and the club’s 2014 competitive balance draft pick.

Come game time, Gonzalez — one of the Orioles’ most dependable starters — struggled mightily for his second straight start.

Gonzalez allowed a career-high nine runs on nine hits, forced from the game after allowing five unearned runs in the fourth inning.

The Astros (37-70) plated all five of their runs in the fourth — including Jason Castro’s first career grand slam — after a two-out error by shortstop J.J. Hardy.

After recording eight straight quality starts, Gonzalez has been roughed up for 15 runs over his past two starts. He allowed a season-high six earned runs over 4 2/3 innings in a 7-1 loss in Kansas City on Thursday.

Wednesday’s outing was his shortest major league start since lasting just 2 2/3 innings in a 10-1 loss to the Tampa Bay Rays on July 25, 2012, when he allowed seven earned runs.

This is the first time in Gonzalez’s major league career than he’s failed to make it out of the fifth inning in back-to-back starts.

The Astros hit four homers off Orioles pitching, including Robbie Grossman’s first career major league homer, a two-run shot of Gonzalez in the second inning that landed on Eutaw Street. With it, he became the second Astros player to homer onto Eutaw Street (Lance Berkman did it on June 18, 2008).

— Baltimore Sun