Of the 28 players chosen on the first round of the NFL draft last April, only 11 are starting for their teams entering the fourth week of the season.

Keith Gary, Pittsburgh's first-round selection, and David Overstreet, Miami's No. 1, signed with the Canadian Football League. Booker Moore (Buffalo) is sidelined because of illness. Leonard Mitchell (Philadelphia) missed most of training camp with an injury.

The biggest early flop may be Cincinnati's David Verser, who is a third-string wide receiver and has yet to catch a pass. Tight end Willie Scott (Kansas City), tackle Howard Richards (Dallas), tackle Brian Holloway (New England), tackle Curtis Marsh (Oakland), cornerback Ted Watts (Oakland), linebacker Mel Owens (Los Angeles), quarterback Rich Campbell (Green Bay) and defensive back Dennis Smith (Denver) have been unable to make veteran lineups.

Some rookies have been outstanding. George Rogers (New Orleans), the first man picked, already has set a Saints' single-game rushing record. Linebacker Lawrence Taylor (Giants) blitzed 15 times against the Redskins two weeks ago. Safety Ken Easley is Seattle's leading tackler, Randy McMillan has given Baltimore a much-needed fullback, Mark May filled the Redskins' left tackle void, defensive back Ronnie Lott is the standout of the 49er secondary, James Brooks has provided San Diego with a fine backup to Chuck Muncie and Hugh Green had delighted Tampa Bay at linebacker.

The other first-round picks who are starters are Freeman McNeil of the Jets, Bobby Butler of the Falcons and Donnell Thompson of the Colts.