ATLANTA -- Tevin Washington did just enough for Georgia Tech to overcome its least impressive showing of the year.
Washington ran for 120 yards and two touchdowns and No. 13 Georgia Tech had just enough to beat Maryland 21-16 on Saturday.
Yellow Jackets coach Paul Johnson said the Terrapins "whipped our tail pretty good in the end."
Georgia Tech (6-0 overall, 3-0 Atlantic Coast Conference) matched its wins total from 2010, when it finished 6-7. The Yellow Jackets averaged almost 52 points in their first five wins and began the day ranked first in the nation in rushing and second in scoring.
Johnson said he'd have to look at the film to determine why his high-scoring offense managed only one touchdown in the second half.
"Offensively, we struggled, never got any continuity," Johnson said. "It was a myriad of things, and we will have to watch the tape, but we didn't do very many good things today."
A season-high eight penalties for 63 yards and poor passing helped hold back the Georgia Tech attack. Johnson called the penalties, most on the offensive line, "ridiculous."
Maryland unveiled a bold uniform combination of mustard yellow, black and maroon. For three quarters the Terrapins were all dressed up with no place to go. Maryland managed only 176 yards and a field goal through three quarters.
Then Brown, unable to move the team through the air, led the comeback with a big run.
Brown showed his speed on a 77-yard touchdown run down the Georgia Tech sideline early in the fourth quarter for Maryland (2-3, 1-1). Davin Meggett, who had 86 yards rushing, scored from the 1 with 7:33 remaining to cut the lead to 21-16.
But Maryland was stopped on fourth-and-8 from its 46 on Brown's incomplete pass with 2:31 remaining, ending its comeback bid.
Brown was 4 of 17 passing for 36 yards and an interception. He had nine carries for 124 yards.
O'Brien was replaced after completing only 1 of 6 passes for 17 yards and an interception.
"I just felt like we needed a little bit of a spark," said coach Randy Edsall of his decision to make the change. "I thought that (Brown) did give us a spark. We will watch the film and evaluate from there."
Washington had scoring runs of 7 yards in the first quarter and 3 yards in the third. Orwin Smith had a 10-yard scoring run in the second quarter.
Maryland's only points in the first three quarters were Nick Ferrara's 30-yard field goal at the end of a 14-play drive on the Terrapins' first possession.
Washington was Georgia Tech's leading rusher, but he struggled as a passer as he completed only 6 of 19 passes for 114 yards and an interception.
"I think offensively we came out flat in the second half," Washington said.
"On my part, I know I did a poor job in the reads in this game running the option."
Washington had 32 carries -- too many, according to Johnson.
"He needs to learn to pitch it every once in awhile or hand it off," Johnson said.
Despite the problems, Johnson stuck with Washington while Maryland is left with a possible quarterback controversy.
Edsall pulled O'Brien after the sophomore's second-quarter interception, his sixth of the year.
Brown took over and remained in the game after he was picked off by Rod Sweeting in the end zone in the third quarter.
Georgia Tech led 14-3 at halftime but wasted two second-quarter chances to stretch the lead.
Linebacker Quayshawn Nealy, making only his second career start, intercepted a pass from O'Brien to give the Yellow Jackets the ball at Maryland's 28. A false-start penalty helped stall the drive after one first down, and Justin Moore was wide left on a 34-yard field goal attempt.
Maryland turned to Brown on its next possession.
Georgia Tech had a 13-play drive at the end of the first half end when Washington's pass for Stephen Hill was intercepted by Dexter McDougle in the end zone.
Maryland left guard Andrew Gonnella was taken off the field in an ambulance after a left leg injury in the fourth quarter.
With most Maryland players standing or kneeling on the field, the game was delayed for about 15 minutes as medical personnel from each team worked in a circle around Gonnella.
"We're saddened and upset about what happened," said Edsall, who confirmed Gonnella was taken to the hospital but said he had no details on the injury.
"If he can't come back, he will be sorely missed," Edsall said of the senior. "He's been a great leader for us and a guy who loves the game of football. Now we just need to take a piece of him with us and go back out there and play for him."