If the role of quarterback is the most important position in all of sports, then the role of backup quarterback has to be the most difficult task.
Limited reps, little or no preparation and the trade of carrying the clipboard to carrying the expectations of an offense at a moment's notice. All in a day's work.
The Washington Redskins have a good one in Kirk Cousins, who has shown that he can come off the bench and be effective in relief of Robert Griffin III.
He proved it last year in his gutsy comeback performance vs. the eventual Super Bowl champion Baltimore Ravens. Cousins stepped up and delivered an 11-yard touchdown pass with 36 seconds left in the game and then ran in the two-point conversion to tie the game at 28. The Redskins would go on to win 31-28.
But not all games end in celebration for backup quarterbacks. Cousins entered Sunday's contest against the Denver Broncos in the middle of a quagmire of which he was unable to help.
Cousins spoke to the media after the game and asserted his goals in future situations off the bench.
"I have to be ready at a moments notice. I try to stay warm on the sideline the best I can," he said. "I try to stay mentally into it the game the best I can. Coaches explain to me that there is expectation that the standard of performance would drop when I go in and I don't expect that of myself either.
"While that is a lot to ask, that is certainly the expectation, I go in there expecting to meet their expectation."
Cousins came into the game and connected with Jordan Reed for 17 yards and the first down. From there, he completed only half of his next eight passes, throwing two interceptions and taking a jarring hit from Broncos defender Wesley Woodyard.
Cousins spoke about the hit and the reactions he received by people who saw it on TV.
"It all happened so fast, I feel like I have taken hits like that before and when I got up I didn't think anything of it. Just patted him on the helmet and said good hit and kept going," he said. "Right after the game, I saw that I got a lot of texts from people not saying anything about the interception, not saying anything about the loss but all they said was, 'Boy that was quite a hit.'
"It must have looked worse than it was. I didn't have any repercussions from it, but it did look pretty bad once I saw it."
Cousins looked sharp in first-string duties this preseason and did nothing to threaten his role as the backup quarterback on gameday. He explained what it takes to be a backup and the difficulties he faces going into a game.
"I think both [starting and backup] are difficult. The game as a quarterback is so mental, that's why guys who have played so long have success," he explained. "Physically, when you haven't been in, it's tough to get warm, get into the flow of the game it's tough to jump right in and have success.
"It's a little bit of both but there is really no excuse, I have to be ready regardless of the situation. That's the job I signed up for."
For Cousins, Sunday was another learning experience on his path to success. He understands his role: help the team maintain a consistent level of play on offense.
Cousins made no excuses about his disappointing performance and knows he must play better when his opportunity arrives.
"That's what I signed up for; it's the job that I have to be able to do."