Sweat and disappointment covered Darryl Grant's face today, proving that change can be a maddening experience.

"It didn't go great, I know that. In fact, it went pretty bad," Grant said after this morning's Redskins practice.

For the moment, anyway, Grant is the team's starting offensive right guard. Until Thursday, he was the team's starting defensive right tackle.

Thursday, however, it was learned that Mark May, starting offensive right guard, had suffered a partially torn triceps muscle, which will sideline him for at least two to three weeks.

So Grant, a 6-foot-1, 275-pound bundle of versatility who played the offensive line in his rookie Redskins year of 1981, jumped back across the line of scrimmage to fill the void.

"It's like a whole new world. It's like writing with your right hand all along, getting used to it, then having to start writing with your left hand," Grant said. "It's tough."

Redskins coaches say they have confidence in Grant. Because there are no experienced offensive linemen on the National Football League's waiver wire in these days when teams are still taking stock and because the Redskins have no experienced reserves on the offensive line, Grant is the starting right guard, for now.

Some team officials fear that the injury to May's triceps muscle, which is crucial to the uppercutting arm motion of a pass-blocking offensive lineman, could keep him out longer than two to three weeks. When May returns to health, Grant likely will return to the defense, although he might play offensive right guard in some situations.

Right now, nobody knows for sure. It can be called a training camp minicrisis.

"Don't count me out. I'll be there by Dallas (the season-opener, Sept. 5) at the latest," May said today. May is Grant's training camp roommate and Thursday night he spent a half-hour diagramming offensive sets for Grant.

"A coach is always on the ragged edge when it comes to injuries," said Coach Joe Gibbs. "Darryl is unsure of some things (on offense) right now, but he's intelligent. He's been there before. He's got some recall."

"We're looking at this as a loan, nothing permanent," said Richie Petitbon, the coach who runs the Redskins' defense. "Everything depends right now on how Perry Brooks and Pat Ogrin (defensives tackles) come along and how May's injury comes along."

Today, the frustration set in with Grant during one-on-one pass-blocking drills. Each time Grant raised his arms, the duty of an offensive lineman, somebody hit him, then swept past him.

First, Dexter Manley, the defensive end with the Mohawk haircut, rushed past Grant. Then Perry Brooks, the defensive tackle with the "Sweet P" tattoo on his right forearm, went by. Then, Manley did it again. Then, Brooks did it again.

"I feel like a third-year rookie," said Grant. "The approach, the angles, squaring up against the linebackers. It's all so different . . . And I had forgotten what it was like with (Offensive Coordinator Joe) Bugel. He's so intense. He's a perfectionist. He wants everybody's blocking technique to be the same: perfect. He was on me today--as usual. It came back to me real quick what it was like playing for him."

Bugel said, "Darryl is the kind of guy who hates to make mistakes. He was embarrassed out there a couple of times by Dexter and Brooks . . . His techniques are a little rusty, but he's got all the toughness you need. He'll get there."

Grant, 23, has served as a yeoman example of a football yo-yo. He has not played the same position for consecutive seasons for the past seven years (including four at Rice). He played the offensive line in his rookie year with the Redskins but was converted to defensive tackle prior to last year.

Meanwhile, there is opportunity for defensive tackles Brooks and Ogrin, the second-year reserve who has impressed the coaches in camp. Last year, Brooks was the Redskins' starting defensive right tackle until breaking his leg in the fifth game of the year against Dallas.

Brooks is known as a quality pass rusher. His problem has been frequent injuries. Brooks is 6 feet 3 and 280 pounds now and, Petitbon said, "He has a ways to go to get into shape. He has to lose another 10-12 pounds."

"I just want to get in a full season to show management and the coaches that Perry Brooks is not injury-prone," said Brooks. "If I get 15 sacks this year, beautiful. I just want to get rid of all that bull and second thoughts about me being injury-prone and me only being able to play on passing downs."

"My quickness is back in my knee for the first time since college," said Ogrin, 6-5 and 265.

As smiles creased the faces of Brooks and Ogrin today, Grant huffed in the heat, playing yo-yo football once again. As beads of sweat ran down his cheeks, Grant adjusted his portable tape player, saying solemnly, "Isley Brothers, Frankie Beverly and Culture Club. It's all slow music. At this point, that's what I need."