SAN DIEGO (AP) — The first 15 seconds of Mike McCoy's head coaching debut were just about perfect.
The final 15 minutes or so were a perfect example of everything he's got to fix about the San Diego Chargers.
Randy Bullock kicked a 41-yard field goal as time expired, and the Houston Texans rallied from a 21-point deficit in the second half for a 31-28 victory over the Chargers on Monday night.
"This was a tough one, obviously," McCoy said. "When you play a good team like the Houston Texans, you have an opportunity when you're up 28-7. You have to put the game away."
The Chargers led 7-0 just 15 seconds into McCoy's first game, intercepting Houston's first pass and throwing a TD pass on their first offensive snap. Philip Rivers threw four touchdown passes in a tantalizing start in the system run by McCoy, the offensive guru hired away from division rival Denver to revitalize a stagnant franchise.
San Diego was three touchdowns ahead after the opening series of the third quarter, and led by 14 points heading to the fourth. But everything came unraveled as a team that blew five halftime leads last season did it again, with Matt Schaub and the Texans' veteran defense taking control in the fourth quarter.
Welcome to San Diego, coach.
"The effort was there," McCoy said. "They did a nice job. We just didn't finish it. It comes down to not finishing a football game."
Ryan Mathews caught a 14-yard TD pass on San Diego's first snap, while Eddie Royal made two TD catches and Vincent Brown had another for the Chargers. But the Texans shut out San Diego over the final 25 minutes, with Brian Cushing returning an interception 18 yards for his first NFL touchdown with 9:30 to play, and Schaub engineered the final 36-yard drive to set up Bullock, who coolly nailed his first NFL field goal.
Plenty of fans were reminded of last season's lowlight, when San Diego blew a 24-0 halftime lead in its last Monday night game against McCoy's Broncos last October.
"You lose this way, and it stings a little more," Rivers said. "It's disappointing we didn't finish the game, because we had control. You've got to play all four quarters."
After two straight division titles and playoff trips, the Texans have ample experience in handling trouble together. Schaub provided steady leadership, and their vaunted defense held San Diego to 90 yards — just 7 on the ground — in the second half.
"There was no doubt in my mind that we were going to win that game," said Andre Johnson, who had 12 catches for 146 yards. "Even in the third quarter, we didn't come out playing that great, but we got it together and made it happen."
While the Chargers showed promise, the Texans began a season of Super Bowl aspirations with a gritty comeback befitting a defending two-time AFC South champion club that got off to an 11-1 start last season.
Schaub recovered from that tipped interception to throw three TD passes — two to tight end Owen Daniels — in the final game of the NFL's opening weekend.
"Once you put a score on the board, then another, and the defense gets a stop, the big turnover, it just builds," said Schaub, who bounced back from an interception on Houston's first play to pass for 346 yards. "Momentum keeps building, and you can feel that energy, and it's contagious."
McCoy was hired to jump-start a team that has missed the playoffs for three straight years, leading to the dismissal of Norv Turner and general manager A.J. Smith after the Chargers' first losing season since 2003.
Rivers looked comfortable early on in McCoy's latest version of an offense that was tweaked for Tim Tebow and Peyton Manning in Denver in the past few seasons. Rivers took most of his snaps in a shotgun, and San Diego used short drops and quick routes to keep Rivers out of trouble after he took 49 sacks last season.
But Cushing came up big in his first game since missing most of last season with a knee injury and then signing a six-year, $55.6 million extension last week. Rivers' under-pressure throw was snagged by Cushing, who got up from his diving catch and rumbled into the end zone.
Schaub's first pass was tipped into the air by Jarret Johnson, and 330-pound defensive tackle Cam Thomas gathered it in. The San Diego crowd was still cheering when Rivers threw down the Houston sideline to Mathews, who dived in for a score.
"We've just got to keep the pedal down," Mathews said. "You can see we can put up points, and our defense is looking great."
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