Mark Alwin reeled off four birdies on the front nine today to erase much of an eight-shot deficit entering the final round and went on to win his second Mid-Atlantic Open golf championship at Evergreen Country Club.

The assistant pro at Woodholme Country Club in Pikesville, Md., repeated his 1978 victory by finishing with seven birdies and a five-under-par 67. His 54-hole total of 209, five under par, was three shots better than runners-up Ron Powell of the host club and Larry Rentz of Lanham.

Finishing in a tie for fourth was Fred Funk of College Park, who blew to a seven-over 79 today after shooting 68-66 in the first two sessions for a three-shot tournament lead. He tied at 213 with Clement King of Farmington, Va., who shot a 76 after being only three shots back during the final round.

"I just started badly and putted badly all day," Funk said. "I was three over after four holes and I never really recovered, although I brought it back enough so that I was only one over at the turn."

Once he got an opening, however, Alwin didn't let up. He posted birdies on the first, fourth, sixth and seventh holes to make the turn in 32, four under, and added birdies on the 12th, 15th and 18th holes to complete the comeback.

"I never rallied from this far behind in this big a tournament before," Alwin said. "When I won the Middle Atlantic Open and Middle Atlantic PGA tournaments in '78, I was in there all the way."

Alwin had plenty of unwilling the first two rounds shot themselves out of contention emphatically today.

The victory was worth $3,000 to Alwin, consistently one of the better Mid-Atlantic players, who is stepping up his area play once more after going on the tour for a year.

Funk, a pro for only seven months and not yet a full-fledged PGA member, won $2,000.