With the chance to add to a 2-1 lead with the Orioles' top hitters due up, left fielder Nate McLouth took off from first base in an attempt to steal his 23rd base of the year.
But as he popped up from his slide at second, McLouth's foot slipped off the base, and Los Angeles Angels shortstop Erick Aybar applied the tag on the throw from catcher Hank Conger, and McLouth was ruled out.
If McLouth was successful, he would have been standing on second base with one out and Nick Markakis at the plate with Adam Jones and Chris Davis waiting in the wings. Instead, the bases were empty with two outs for Markakis, and the Orioles weren't able to build on their lead in the eventual 9-5 loss Wednesday afternoon.
Both McLouth and manager Buck Showalter contested umpire Joe West's call at second base, as it appeared Aybar never tagged McLouth when his foot slipped off the base.
When McLouth was asked about the call after the game, he said he couldn't tell if he was safe.
"I don't know," McLouth said. "I [haven't] watched the replay yet."
The caught stealing snapped a streak of 19 successful stolen base attempts for McLouth, which was the longest active streak in the majors entering Wednesday. The streak was also the third-longest in Orioles history behind Brady Anderson's 36 consecutive steals in 1994-95 and Luis Aparicio's 21 straight successful attempts in 1963.
McLouth was also attempting to tie a career high in steals for a season. He stole 23 bases for Pittsburgh in 2008, and his second highest total was also 22, coming in 2007 with the Pirates.
This was just the third time McLouth was caught stealing in his 111-game Orioles career. As an Oriole, McLouth is 34-for-37 in stolen base attempts. He was caught once in 13 attempts after coming over from Pittsburgh midway through 2012.