The two-hour, controlled scrimmage in muggy Byrd Stadium yesterday was the Maryland football team's toughest workout of the season, according to Coach Jerry Claiborne. It also was a showcase for the Terrapins' backup talent.

After starting quarterback Bob Milkovich was forced out of action early with a slight shoulder bruise, Brent Dewitz came in and completed four of seven passes against the scout team. Boomer Esiason did even better, completing five of eight passes, including a nine-yard scoring pass to tight end John Tice.

Running back Charlie Wysocki scored on a one-yard run and carried 12 times for 52 yards. His backup, tailback Tim Whittie, was impressive, gaining 64 yards on 10 carries, including runs of 16 and 17 yards.

Jesse Atkinson, a sophomore walk-on kicker from Crossland High School, was the day's leading scorer with field goals of 34 and 47 yards and two extra points.

At Annapolis, tailback Eddie Meyers ran through Navy's experienced, first-string defense yesterday at the Navy-Marine Corps Memorial Stadium for 144 yards on 32 carries, but Coach George Welsh still thought his defense had a good day. "The defense really picked things up today," said Welsh. "It's about time it did something."

Welsh had both junior quarterback Tom Tarquinio and sophomore transfer Marco Pagnanelli working at quarterback with the first offensive unit. Tarquinio was 11 for 21 for 141 yards. Pagnanelli, who directed the offense in the second half, was seven of 18 for 66 yards.

Starting quarterback Raymond Gray and his backups, Sandy Nichols and freshman Brain Sloane of McKinley, all gave Howard Coach Floyd Keith a reason to be pleased yesterday after a 1-hour-15-minute controlled blue-white scrimmage at Howard Stadium. But the reason the trio looked so impressive may be Keith's biggest worry as the Sept. 12 opener with Cheyney State approaches.

Watching the scrimmage out of uniform were safeties Chris Jackson (stomach problems) and Jimmy Biggs (bone chip in knee). Keith said he was hopeful both problems, among a rash of preseason injuries the Bison have suffered, would be remedied before the opener.

Last year, the Bison had their first winning season since 1975 (6-2-2). Howard's pass defense was ranked first among NCAA Division I AA schools. Depth is a major concern for Keith this year at many positions, including the secondary, which can ill afford to be without both Jackson and Biggs.

Returning all Mid-East Athletic Conference right guard John Bilberry and center Keith Hill opened several good holes during the scrimmage for Gray and tailback Bufus Outlaw. Gray, a senior, is trying to fill the void of Ron Wilson, last year's MEAC total offense leader and offensive player of the year.