KANSAS CITY, Mo. -- Miles Austin looked nothing like a backup making his first career start.
Stepping in for injured wide receiver Roy Williams, Austin caught 10 passes for a franchise-record 250 yards and scored the winning touchdown in overtime of the Cowboys' 26-20 victory Sunday over the winless Kansas City Chiefs.
In dooming the Chiefs to their 28th loss in 30 games, Austin erased the record of 246 yards that Hall of Famer "Bullet" Bob Hayes set against Washington almost 39 years ago.
"It's a feeling that's unbelievable," he said. "It's amazing. I never seen that coming today. I was ready today, but you never expect a huge game like that."
Austin's tackle-breaking 59-yard catch-and-run from Tony Romo gave the mistake-prone Cowboys a 20-13 lead over the Chiefs with 2:16 left. Then after Matt Cassel's 16-yard TD pass to Dwayne Bowe tied it 20-20 with 24 seconds to go in regulation, Austin got free on a 60-yard scoring play on Dallas' second possession in overtime.
Each time, he broke the tackle of cornerback Maurice Leggett.
"It's very frustrating," Leggett said. "But we also have to focus on the bigger stuff so we can get better each and every day. Don't take big jumps and focus on getting 2 percent better every day."
Kansas City (0-5) is winless for 315 days and has lost eight in a row at Arrowhead Stadium, where the Chiefs were nearly invincible during the 1990s.
"I thought the guys fought hard in all phases," said coach Todd Haley. "I know the guys are hurting."
Austin is the third Cowboys receiver when Williams is healthy. But he was unstoppable against the Chiefs, who led most of the game but couldn't take advantage of the many opportunities the Cowboys kept handing them.
"I just wanted to show people I'm ready to play. I wanted to show my teammates that I want to contribute as much as I can," he said. "I was able to do that."
Dallas (3-2) was penalized 13 times for 90 yards and Romo overthrew several open receivers. Other passes were dropped. Dallas also muffed a punt and missed a field goal attempt.
"Our guys fought the whole game but we didn't do all the right things," said coach Wade Phillips. "There are things we need to work on, but the bottom line is winning and guys coming through."
So has Austin cracked the starting lineup?
"We are going to try and keep him playing," Phillips said. "There is no doubt about that."
Late in the fourth quarter, Austin caught Romo's pass, broke loose from tackles by Leggett and safety Mike Brown, and sped 59 yards to give the Cowboys their first lead of the day.
Then Cassel swept the Chiefs down the field, hitting Bowe in the end zone on fourth-and-7. Ryan Succop, who had a 53-yard field goal attempt blocked by Jay Ratliff right before Dallas' last TD in regulation, kicked the extra point for the tie.
Romo was 20 for 34 for 351 yards and two TDs. Cassel, still winless since being traded from New England, was 23 for 41 for 263 yards.
Romo said he noticed on the last play that the defensive back was "really tight on Miles."
"He tried to jump it, so I had to keep it outside a little more than you'd normally want to, but Miles did a good job of continuing to come back," Romo said. "If you take that chance as a corner, the possibility is there. I was glad to see Miles take off. It was really exciting and rewarding."
After Brown recovered Romo's fumble on the Dallas 16 in the second quarter, Mike Vrabel, a 13-year veteran linebacker, caught a 1-yard TD pass, giving him 11 touchdowns in 11 career catches.
The Chiefs won the coin toss and received in the overtime but failed to get close enough for a field goal attempt.
"You fight so long for that victory and it comes down to the wire and you end up losing. It's like it kills everything," said Chiefs defensive lineman Tank Tyler.
Neither quarterback threw an interception. ... Umpire Bill Schuster left the field for several plays in the first half. Schuster was standing in front of the pile when Kansas City LB Tamba Hali rolled up on him from behind, knocking him flat. ... Cassel has thrown a TD pass in four straight games and gone 100 consecutive throws without an interception.
The Atlanta Falcons have agreed to a five-year contract extension with wide receiver Julio Jones. Sources say he will receive $71.25 million total, with $47.5 million guaranteed.
Randall Cobb, who took over for Jordy Nelson as the Packers' No. 1 receiver, was injured on the third play in Saturday's 39-26 preseason loss to the Eagles and was examined in the locker room.
Redskins quarterback Kirk Cousins entered with a chance to secure a starting job and exited the same way after going 20-for-27 for 190 yards and a TD in Saturday night's win vs. the Ravens.
Bengals QB Andy Dalton left Saturday's 21-10 preseason win over the Bears as a precaution with a neck injury that appeared to happen on his first and only series of the night.
Buffalo Bills coach Rex Ryan will decide on his starting quarterback Sunday but will not make his decision public, hoping to keep the Indianapolis Colts -- the Bills' Week 1 foe, in the dark.
Baltimore Ravens wide receiver Steve Smith and Washington Redskins cornerback Chris Culliver were ejected with less than a minute left in the first quarter of Saturday night's preseason game.