Closer Jordan Walden was summoned to get the five-out save, but Matt Wieters singled on the first pitch thrown to him - a 96 mph fastball - and Jones raced home with the tying run.
Hunter allowed six runs and 10 hits in 6 1/3 innings. Left-hander Michael Gonzalez replaced him and retired both batters he faced to end the seventh.
Gonzalez hasn't allowed a run in 10 straight appearances and 15 of 16. He's looking like one heck of a situational lefty.
Admit it, you're slightly intrigued by the idea of re-signing him over the winter. You just don't want to say it out loud.
Update: The Orioles scored twice in the top of the 12th to take an 8-6 lead. Too bad it wasn't enough.
I'll get to the meltdown in a minute.
Jones collected his fourth hit, a two-out RBI single to right field off Fernando Rodney. J.J. Hardy raced home on a throwing error.
The Orioles looked like they had tied the series, but wait...
Kevin Gregg gave up a leadoff single and hit a batter. Josh Bell fielded Hank Conger's bunt and threw the ball away, allowing a run to score. Bell made a lunging stop of Peter Bourjos' grounder, looked to third and threw late to first, loading the bases with no outs.
Alberto Callaspo walked to force in the tying run and force Gregg out of the game. Once again, he failed to retire a batter - five this time, six in an outing last weekend - though Bell deserved some of the blame tonight.
Troy Patton replaced Bell, and Bobby Abreu hit a sacrifice fly to center field.
Angels 9, Orioles 8
Jim Johnson tossed three scoreless innings in his longest outing in three years. He didn't allow a hit, walked one, struck out two and threw 35 pitches.
Chris Jakubauskas retired the side in order in the 11th before Gregg replaced him.
The Orioles still haven't won a series since June 24-26. They have no shot in this one.