Rob Gronkowski Confirms Working Out with Tom Brady, 'It Was Great!'

Rob Gronkowski and Tom Brady are back together -- at least they were on Monday -- with Gronk telling TMZ Sports the two worked out together at UCLA!

"It was great working out," a slimmed-down Gronk told us at his $50k Charity Challenge basketball game at Pauley Pavilion.

"Tom needs someone to throw to so, you know, he calls Mr. Reliable Robbie G the one and only!"

Rob ran routes and caught passes from TB12 at the field at UCLA, where Tom usually works out while in L.A. for the off-season. Gronk is in town for his charity event, which raises money for Teen Cancer America. He's also expected to attend the ESPYs on Wednesday.

Of course, the workout with Tom begs the question ... will Gronk come…