Defending champions Butch Mielke and Buddy Peoples survived a sudden-death playoff to win their opening-round match, then beat Dick Hill of Columbia and Tim Vigotsky of Evergreen in the quarterfinals of the Belle Haven Four Ball golf tournament yesterday. They were seven under par for their two matches.

In this morning's semifinals, Mielke and Peoples face brothers Charles and Steven Hall of Tantallon. The other semifinal matches medalists Regan O'Rourke of Bethesda and Wade Heintzelman of Washingtonian against Glen Barrett of Penderbrook and Gary Reedy of Reston South. The final is this afternoon.

American University students O'Rourke and Heintzelman appeared to have their quarterfinal match in hand against Colin Clasper and Dan Ramsey, but Ramsey sank winning birdie putts of 15 feet at 17 and 25 feet at 18 to force the overtime. The match ended when Ramsey three-putted the second extra hole.

Mielke, of Wicomico, and Peoples, of Crofton, edged Congressional's Clayton Eisinger and John Murdock on the first extra hole to win their morning match, Mielke sinking a 12-foot birdie putt.

Mielke's deft putting was on display again in the afternoon. He hit an eight-iron second shot to within four feet of the cup at the 14th hole and sank the putt for a 1-up advantage. Mielke then sank a 12-foot winning birdie at the par-5 16th hole and the match ended when both teams parred the par-3 17th hole.

O'Rourke almost made a double eagle-2 on the par-5 fourth hole in his morning round, in which he and Heintzelman edged Tom Walsh of Montgomery Village and Ron Rhodes of Kenwood, 1 up. O'Rourke's second shot, with a three-wood, traveled well over 200 yards and the ball lipped the cup but did not drop. The four-inch tap-in for eagle pulled his team even.

In the other quarterfinal matches, the Hall brothers defeated Bruce Benedict and Dan Disrud, 3 and 2, while Barrett and Reedy eliminated Jim Castagna and Mike Toomey, 2 up.