TORONTO (Reuters) - A pre-game batting session helped John Buck smash three home runs in Toronto's 6-3 victory over the Oakland Athletics on Thursday, ending the Blue Jays five-game losing skid.

The Toronto catcher rallied his team out of a 3-0 hole with a solo homer in the third inning and a three-run blast in the fourth that gave the Blue Jays a 5-3 lead.

Entering the game with just one home run this season, Buck added another solo shot in the sixth to complete a spectacular performance that included five RBIs.

"I was concentrating on getting my foot down early, getting my hands ready," Buck told reporters. "That (pre-game practice) session really helped. It helped me realize how really early I needed to get ready. Hopefully I can use that reminder."

Oakland (12-11) starting pitcher Justin Duchscherer took his first loss of the year after allowing four runs in three and a third innings before leaving the game with a strained hip.

"I threw a few pitches that didn't feel very good," Duchscherer said after the A's lost their third straight. "It's hard to explain unless you feel it. It feels like a real sharp jolt."

Duchscherer missed all of last season with various injuries, but has started the year well and had gone three straight starts without allowing an earned run.

The Blue Jays (11-12) had a solid starting effort from Ricky Romero, who allowed three runs and struck out six batters in six innings.

Kevin Kouzmanoff opened the scoring for the A's with an RBI single in the first and Jake Fox hit a two-RBI double in the third.

In addition to Buck's burst, Toronto outfielder Travis Snider had two hits, including a solo homer in the third.

(Reporting by Jahmal Corner in Los Angeles; Edited by Patrick Johnston)