Ref explains controversial penalty call on Stefon Diggs in Patriots’ win over Saints

It was a long afternoon for Adrian Hill’s crew at the Superdome on Sunday.
Officiating was a frequent talking point in New England’s 25-19 win over the Saints, and the most head-scratching call of the day wiped out a 61-yard DeMario Douglas touchdown in the first quarter.
A late flag was thrown on Stefon Diggs for offensive pass interference, though the veteran wideout appeared to just be hand-fighting away from the play.
After the game, Hill attempted to explain the call in a pool report with PFWA member Mike Reiss:
Question: What was seen to call offensive pass interference on Stefon Diggs that nullified a touchdown catch by DeMario Douglas?
Adrian Hill: “On that play, we ruled blocking downfield by number eight, early during the play. So, if there is a situation where a player blocks downfield, it’s not a foul until a pass is thrown, so you kind of put that in the bank. And then the pass was thrown downfield later, that created the offensive pass interference.”
Question: The follow up question, mechanically, with the later timing of the penalty and subsequent announcement as both teams had their special teams units on the field, how did that unfold, the timing?
Hill: “The official was processing the play and then he came to me over the O20 (official-to-official communications system). Because it was a long-developing play, he had to rewind back to what happened at the beginning of the play, and process that.”
Diggs was whistled for another offensive pass interference later in the game. Though the second was more conventional, it still appeared to be a borderline call at best. Diggs wasn’t sweating the penalties after the win, but did say he planned to submit the footage to the league.
“I don’t really be tripping, to be honest. I try my best to make plays and catch the ball when they come to me,” Diggs said. “When I get (back) hopefully we can submit them to the league to see if it was supposed to be called or not. But I don’t cry over spilled milk.”