As this season which began with Super Bowl hopes has devolved into a disaster, even the almost always mild-mannered Johnson couldn't keep his cool.
Undrafted free agent rookie Matt McGloin threw three touchdown passes in his first NFL start and the Oakland Raiders extended Houston's franchise-record skid to eight games with a 28-23 victory on Sunday in coach Gary Kubiak's return from a mini-stroke.
Kubiak wasn't on the sidelines, instead coaching upstairs from the booth on doctor's orders two weeks after collapsing at halftime of Houston's game against Indianapolis.
He benched Case Keenum, also an undrafted free agent, for Schaub with Houston trailing by 11 points. Houston cut the lead with two field goals in the fourth quarter and had a chance to take the lead late. But Schaub's pass to Johnson on fourth down from the 8 was broken up in the end zone.
Johnson said the argument came because he "messed up" and didn't finish the play.
"We just exchanged some words," he said. "It's just heat of the moment. Once we came in the locker room we talked about it, left it alone, so I'm not worried about that. Me and Matt have played a lot of football together."
Schaub also brushed off their disagreement.
"It's just emotions, emotions of the game, a culmination of a lot of things, but stuff we'll keep between us," Schaub said.
Johnson is the longest-tenured player on the team after joining the Texans in their second season in 2003, and endured Houston's franchise-worst 2-14 season in 2005. He has a long-term contract and has always said he wanted to finish his career here. But after the game when asked if he wanted to remain with the team in the future, it seemed that he might be growing weary of playing for Houston.
"I'm under contract, so I have to play my contract out," he said. "I can't do anything about that."
It was the first time since 2011 that two undrafted free-agent quarterbacks have started in the same game. The last time came when Kansas City's Tyler Palko met Chicago's Caleb Hanie on Dec. 4, 2011.
Kubiak replaced Keenum with Schaub after Houston's first three drives of the second half all ended in punts. Schaub was terrible early this season and hadn't played since Oct. 13, after he was benched following an injury.
"I knew that Matt could get done some of the things that I wanted to get done real fast and to give us a chance to win," Kubiak said of the change. "So that's why I did it."
Keenum threw for 170 yards with a touchdown and an interception. Schaub had 155 yards passing.
Kubiak wouldn't say who'd start next week.
Houston punted on Schaub's first drive before settling for a 26-yard field goal on the second when the offense stalled after getting a first down at the 10.
A 30-yard field goal cut the lead to 28-23 with about eight minutes remaining.
Rashad Jennings extended Oakland's lead to 28-17 when he plowed over D.J. Swearinger and rumbled 80 yards for a touchdown with 2:26 left in the third quarter. It was the longest run of his career and he finished with 150 yards rushing.
The Raiders regained the lead when Mychal Rivera grabbed a 26-yard touchdown reception to make it 21-17 in the third quarter.
Houston tied it at 14 when Keshawn Martin let a punt bounce off the grass and his chest before scooping it up and dashing 87 yards for a touchdown about three minutes before halftime. It was the longest punt return for a score in franchise history.
Randy Bullock made his first field goal of 50 or more yards with a 51-yarder to give Houston a 17-14 lead just before halftime.
McGloin's first career touchdown came when he hit Denarius Moore on a 5-yard slant to put Oakland up 7-0.
Houston's second miscue came when Keenum threw his first career interception as he was being hit by Stacy McGee. It broke a streak of 105 pass attempts without an interception for Keenum.
The Raiders immediately took advantage of the error when McGloin connected with Rod Streater for a 16-yard touchdown on the next play to make it 14-0.
NOTES: Former Presidents George W. Bush and George H.W. Bush were on the field before the game and the younger Bush did the coin flip. ... McGloin is the 17th quarterback to start for the Raiders since the start of the 2003 season.
AP NFL website: http://www.pro32.ap.org