Chicago catcher Marvis Foley surprised everybody, including himself, when his 12th-inning homer gave the White Sox a come-from-behind 5-4 triumph and knocked the Baltimore Orioles out of first place tonight at Memorial Stadium.

After all, the left-handed batter has never had much success against lefthanders and his victim, Tippy Martinez, had not served a gopher in nearly two years, a streak of 66 games and 123 2/3 innings, going back to May 23, 1978.

With a two-strike count, Martinez served him one of those dreaded curves. "I've never hit a homer to win a game in my life," Foley said of his first shot of the season. "I kept looking fast ball, fast ball. I have trouble against left-handers, but the ball I hit was a curve. One 0-2, I thought he'd bust me, but I was already stepping out (on the curve) when I hit it.

"I couldn't believe it. When I rounded first, I thought he'd catch it. When I hit second I saw it was out . . . 309 1/2 (it cleared the 309-foot marker)."

Foley's homer climaxed a Chicago effort in which the White Sox wiped out a 4-0 deficit with home runs by two regulars with a combined batting average of .137. And Manager Tony LaRussa came out looking like a genius with some late-inning moves which thwarted Bird rallies.

The Orioles' Jim Palmer breezed through five innings before the Chisox combined three singles for a run to narrow the Orioles lead to 4-1 in the sixth. Then in the seventh, Oriole nemesis Jim Morrison, hitting .214, cleared the left-field fence with his first shot of the year and Harold Baines with one hit in his 23 major league at bats, pulled a home run down the right-field line to narrow the Bird advantage to 4-3.

Tim Stoddard ended the rally and pitched a strong eighth before Baines and pinch hitter Thad Bosley and Mike Squires strung together singles to tie the score.

Meantime, Chicago reliever Rich Wortham had stilled Baltimore bats. Wortham, whom LaRussa mysteriously brought in after first reliever Randy Scarberg opened the seventh with a strikeout, pitched four innings of one-hit relief. He retired the first eight batters he faced.

Baines led to Wortham's departure in the 11th, playing Doug DeCinces' easy one-out fly to right into a threebase error. LaRussa brought in Ed Farmer, who intentionally walked Gary Roenicke. But the possible double play was erased when Roenicke took second base unchallenged.

Farmer pitched to May rather than walk him to set up another double play. The Orioles designated hitter responded with atappert to the mound and Farmer caught Murray a at the plate. Then Rick Dempsey lined a shot off Farmer's leg, but shortstop Henry Chappas was able to throw Dempsey out at first.

"I could give you a reason for each move, but I'm an intuitive manager; you really wouldn't want to hear them," LaRussa said. "I took out Scarberry because Bumbry (the next batter) could steal on him if he got on.I took out Wortham after the error because he had to be shaken. And I didn't walk May because I almost never walk the bases loaded. It puts too much pressure on the pitcher."

Foley, who came in to catch the ninth inning, saved the game with stops of one pitch in the dirt and another over everybody's head to May in the 11th with Murray on third.

"I enjoy being a defensive catcher," Foley said. "If I do everything right behind the plate and go 0 for 4, I think I've done my job."

The Orioles, who managed only five hits, fell 15 percentage points behind Milwaukee in the American League East. They wasted back-to-back homers by DeCines (with Murray on) and Roenicke in the fourth.

hey also had the bases loaded with two outs in the 12th when DeCinces ground out to short. That pushed the White Sox bullpen's season stats to 20 scoreless innings against the Orioles.