He held the ball too long, allowing a highly effective Rams pass to intimidate the Vikings’ overmatched offensive line.
He forced a pass to Jordan Addison that resulted in an interception, without seeing Jalen Nailor wide open downfield.
He fumbled while taking a sack, resulting in a Rams defensive touchdown.
With Darnold’s implosion, the Vikings were going to need defensive or special teams touchdowns to stay in the game, but when they got one — on Brian Cashman’s fumble return — it was negated because Stafford had made a half-hearted, backhanded throwing motion that was judged to be a successful attempt and therefore a failure.
Darnold cost himself a lot of money on Monday and opted out of becoming the Vikings’ long-term starter.
Which, in the long run, is a good thing.