Plenty of things went wrong for the 49ers in Sunday's 31-7 NFC Championship loss, but their series of unfortunate events got started with one controversial Philadelphia Eagles play that could have gone very differently.
As the replays showed, Eagles receiver DeVonta Smith's 29-yard fourth-down reception in the game's first quarter wasn't actually a catch, but Philadelphia was able to get the next snap of their eventual scoring drive off without the 49ers challenging the call.
So, why didn't coach Kyle Shanahan throw the red challenge flag?
"Because the replay we saw didn’t definitively show that [it wasn't a catch]," Shanahan told reporters after the loss. "... I was going to throw [a challenge flag] anyways, just to hope to take the chances, but they showed one up on the scoreboard that didn’t have all the angles you guys saw, and that looked like a catch.
"So we didn’t want to waste a timeout, which we definitely would have if we didn’t see that, but then I heard they got a couple other angles, and you guys ended up seeing that it was not a catch."
In all fairness, the 49ers didn't have much time to make a decision. Upon standing up after the play, Smith immediately signaled to the Eagles' offense to get down the field in a hurry and get their next play off before the call could be reversed.
"... It’s easy when you get to see it that it’s incomplete, but that other person, myself, in the stadium looking at the screen and all the angles that we had and the time before it was snapped, I don’t know what you guys had, but we couldn’t see that," Shanahan said.
Eagles coach Nick Sirianni applauded Smith for hurrying up the offense after the play, and the decision jumpstarted a series of catastrophic events for the 49ers -- including the Eagles' ensuing go-ahead touchdown on the game's opening drive.
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After winning 12 straight games, the 49ers' final game didn't end in their favor.
And Smith's catch certainly could be on their minds for quite some time.