
Mike Zimmer became the first NFL head coach to challenge a pass interference call during a regular season game on Sunday, but the result was not a positive one for his Minnesota Vikings.
The Atlanta Falcons got the ball at the 2-yard line midway through the third quarter when Vikings cornerback Trae Waynes was called for pass interference on a deep pass from Matt Ryan to Calvin Ridley. Zimmer threw the red challenge flag, but he lost.
— Paid man gets bored (@cjzero) September 8, 2019

The replay official determined that there was not sufficient evidence to overturn the call, which is going to be the standard every time. As former NFL head of officiating Dean Blandino said on the FOX broadcast, it will have to be “blatantly obvious” that there was no contact for an interference call that was made on the field to be overturned.
Fortunately for the Vikings, Ryan ended up squandering the opportunity by throwing a brutal interception in the end zone on a pass he was attempting to throw away. Minnesota had a comfortable lead at the time, so it’s possible Zimmer saw that as an opportunity to test out the new challenge rule.
We already saw one team in the preseason victimized by a horrendous pass interference call that was not overturned upon review, so it seems clear that it is going to be rare.