Atlanta Braves outfielder Hector Olivera was arrested early Wednesday morning after a woman accused him of assault at a hotel outside Washington, D.C.Olivera, 31, has been placed on administrative leave by Major League Baseball, effective immediately per the domestic-violence policy.Police in Arlington, Va., said a woman at the Ritz-Carlton in Pentagon City called them at 6:51 a.m. ET. The female victim had visible bruises and was transported to Virginia Hospital Center in Arlington.Police said Olivera and the woman knew each other but do not know the nature of their relationship."We are extremely disappointed and troubled to learn of the allegations involving Hector Olivera," the Braves said in a statement Wednesday afternoon. "We will continue to gather information and will address this matter appropriately as we determine the facts."MLB announced it has begun an investigation."Consistent with our Joint Domestic Violence Policy, the player has been placed on administrative leave and the Commissioner's Office has begun an investigation," the MLB statement read.The Braves are playing a four-game series in Washington against the Nationals this week, including games Wednesday and Thursday.Olivera joined the Braves last July as part of a three-team trade with the Los Angeles Dodgers. He spent the early part of his career in Cuba before defecting in 2014.Olivera has appeared in six games this season, batting .211 with two RBIs in 19 at-bats. In 2015, he played in 24 games, hitting .253 with two home runs and 11 RBIs.The Braves recalled infielder Daniel Castro from Triple-A Gwinnett to take Olivera's spot on the roster.