Arnold Palmer had eight birdies in a 6-under-par 66 good for a one-stroke first-round lead over Dave Hill and Buck Adams in the $250,000 Senior Challenge at Horseshoe Bend in Roswell, Ga.

Palmer, 58, winless since capturing the Senior Tournament Players Championship in the spring of 1985 but as usual drawing the largest gallery, said, "It was one of the better putting rounds I've had in a long time." He is 21st on the 1987 Senior PGA Tour money list . . .

Trevor Dodds and 1985 winner Danny Edwards shot 67s for the second consecutive day to tie for the lead at the halfway point of the PGA Tour's $300,000 Pensacola (Fla.) Open. They were 8 under par for 36 holes at the 7,154-yard, par-71 Perdido Bay Resort course. Doug Tewell (69-66) tied 18-hole leader John Mahaffey (66-69) at 135 . . .

Fred Gibson of East Potomac in Washington was 1 under par for the 30 holes it took at Rolling Road in Catonsville and defeated Glen Miller of Hidden Creek, 6 and 5, to win his third Middle Atlantic PGA Match Play Championship. Gibson also won in 1979 and 1983.