He played for the Montreal Expos / Washington Nationals, New York Mets, Atlanta Braves, Pittsburgh Pirates, and Arizona Diamondbacks.

Church made his major league debut for the Expos in August 2004, struggling in the 30 games he played in the last two months of the season.

After struggling in the first month of the 2005 season Church was considered a candidate for the Rookie of the Year Award, until he injured himself running into the outfield wall at PNC Park on June 22, 2005.

Church made his return to the starting lineup on June 1, 2008, against the Los Angeles Dodgers, collecting three hits including a home run and a double.

On July 10, 2009, he was traded to the Atlanta Braves for Jeff Francoeur,[2] but was designated for assignment on December 8, 2009, in order to make room for the return of Rafael Soriano.

In 2005, the Nationals suspended Jon Moeller, a volunteer chaplain, and issued an apology after Church, a devout Christian, revealed conversations he had with him about a Jewish former girlfriend.