Lions QB Matthew Stafford is on the verge of breaking the franchise passing record, one that has belonged to Hall of Fame QB Bobby Layne for 55 years. As Greg Garber reports, these two quarterbacks share a whole lot more than a single football record. (1:56)

PITTSBURGH -- Matthew Stafford hit a personal milestone and set a Detroit Lions record all in one play.

Matthew Stafford became the Lions' all-time leader in passing yardage Sunday. Jason Bridge/USA TODAY Sports

Stafford found Calvin Johnson on a deep post route for a 79-yard touchdown with 10:13 left in the first half Sunday against the Pittsburgh Steelers.

It was the 100th career touchdown pass for Stafford, who -- more importantly -- moved atop the Lions' all-time list for career passing yardage.

A fifth-year pro, Stafford passed Bobby Layne, who had 15,710 yards from 1950 to 1958, on the play. Stafford also became the fourth-fastest player to 100 touchdowns in NFL history.

"It's obviously, any time you break a record, it's a humbling experience," Stafford said recently. "It's not something I'm setting out to do every time I go out to a game or whatever it is.

"It's not like I'm going out there trying to break records. I'm trying to win a game. If I do so in the process, obviously I have a lot of respect for the history of this game and this franchise, too, so it's something that when and if it happens, I'm sure I'll reflect on it after the fact."

Stafford finished the game with 362 yards and two touchdowns but completed just 19 of his 46 pass attempts and also threw an interception in the Lions' 37-27 loss.