Steve Grogan, starting his first game in a month, threw for two touchdowns during a 17-point third quarter that gave the New England Patriots a 38-10 victory over the Houston Oilers today.

The Patriots (2-5) had good field position throughout the game, but Houston (4-3) led, 10-7, at halftime. Tim Fox's interception, one of four thrown by Oiler quarterback Ken Stabler, began the Patriots' rally early in the third quarter.

Fox ran back the overthrown pass 20 yards. On the next play, Grogan threw to Stanley Morgan for a 42-yard touchdown. That put the Patriots ahead for good, 14-10, with 2:29 gone in the quarter.

John Smith kicked a 21-yard field goal midway through the period, then Grogan, benched in the Patriots' second game, threw a 10-yard scoring pass to Andy Johnson with 1:21 left in the quarter.

The Patriots completed the rout with fourth-quarter touchdown runs of 15 yards by Vagas Ferguson and 24 yards by Grogan.

"The key wasn't us, but the way they played," said Houston Coach Ed Biles. "It's amazing they don't play that well all the time."

Said Grogan, "We just found a team making the same mistakes we had been making, and we were able to overcome ours."

The Patriots had driven 61 yards with the opening kickoff to score on Johnson's 28-yard pass to Morgan, but fumbled the ball away their next two possessions. Stabler capitalized on the second by passing nine yards to Dave Casper to cap a 74-yard drive.

New England running backs had their best game this season with 244 yards, led by Tony Collins' game-high 89 on 17 carries. Their teammates on defense, ranked last in the league against the run, allowed just 120 yards a week after giving the New York Jets 141. The Oilers' Earl Campbell, best in the NFL after two games of more than 180 yards each, gained 86 on 27 carries; he did not play much in the last quarter.

Grogan, who replaced Matt Cavanaugh in the third quarter in New York, was helped today by excellent field position resulting from short punts by the Oilers' Cliff Parsley and the interceptions. The only time the Patriots had the ball inside their 30 was midway through the fourth quarter, when they started at their 27 and drove to Ferguson's touchdown.

Johnson, a substitute running back who comes in on throwing downs, got his first touchdown this year, but with his first quarter touchdown pass to Morgan now has completed all five of his passes this season, three for touchdowns.