The mentor goes against the pupil on Sunday when Jay Gruden of the Washington Redskins coaches against Sean McVay.
Gruden gave McVay the keys to Washington's offense in 2014 and McVay parlayed his opportunity as offensive coordinator into becoming head coach of the Rams.
McVay, 31, is the youngest coach in modern NFL history.
"Honestly, I didn't think he'd get one this quick," Gruden said, laughing, during a teleconference on Wednesday, adding: "The whole trick is to get in front of a room and I had a feeling that once he got in front of a room, some general managers and some owners, that he would be able to get in there because he's very presentable, he's very knowledgeable, very smart, he's a very loyal guy and very passionate about the game."
Gruden succeeded Mike Shanahan in 2014. He retained McVay and promoted him from tight ends coach to offensive coordinator.
Gruden said he did not want to change the entire system.
"I felt like just from talking to the quarterbacks, instead of me having to tell him ... the call to the quarterback and so forth, it was quicker to let him do it," Gruden said.
The Rams are team coming off a 46-9 victory over the Indianapolis Colts.
McVay said Tuesday that he communicates with Gruden regularly, and that he was looking forward to doing so after Sunday's game at the Coliseum.
The Redskins, with Matt Cavanaugh as offensive coordinator, lost their opener against the Philadelphia Eagles, 30-17.
"We're 0-1 and we've got to try and get our first win and that's the only focus that we have," Gruden said. "We just have to go from there, but after the game, I'm sure I'll talk to Sean.
"Right now it's about trying to get our first win."