“Guardians of the Galaxy Vol. 3″ had a steep fall-off on its second Friday, a 70% plunge to around $15 million. But as a lot of that is attributable to the Thursday “previews” that boosted opening weekend, it’s still on track to clear $50-54 million this weekend, according to Deadline.com.

Middling Thursday night and Friday numbers don’t tell the story of the biggest wide release opening opposite the comic book movie this weekend.

“Book Club: Chapter Two” expects to make a lot of money on Mother’s Day, being a mom/grandmom sort of movie, starring Fonda and Bergman and Steenbergen and The Devine Ms. Keaton. It’s headed towards a $7 million+ weekend, good enough for third place.

“Super Mario Bros. Movie” is still raking it in, with $13 million or so giving it a second place finish. The animated “Road Rally Racers” pic won’t put a dent in it.

“Evil Dead Rise” is adding another $3.5-4 million.

“Are You There God? It’s Me, Margaret” won’t rise much above $2 million, which will put it in a dead heat with the Robert Rodriguez/Ben Affleck thriller “Hypnotic,” which could hit $2.3 million.

As always, I’ll update this as the weekend progresses and more data becomes available.