Burnett (9-4) walked three batters and fanned six while improving to 9-1 lifetime against Baltimore.
Jorge Posada had two hits -- one a solo homer.
Nick Swisher hit a two-run single in a four-run first helped by a key error by Brian Roberts, and both Alex Rodriguez and Robinson Cano had two hits and one RBI for the Yankees, who have not lost since the All-Star break.
Closer Mariano Rivera earned his 28th save.
Baltimore's Adam Jones and Nick Markakis hit solo ninth-inning homers.
Jones had four hits, Markakis had two RBI, and a run scored on Burnett's seventh-inning wild pitch for the Orioles, who have lost 10 in a row at New York.
The losing pitcher was starter Jason Berken (1-8).
Copyright 2009 by United Press International.