Ring City USA Returns Thursday, March 4 at 9 p.m. ET/6 p.m. PT on NBCSN, Bonus Undercard Action Streams Live at 6:30 p.m. ET/3:30 p.m. PT on Twitch  SAN JUAN, Puerto Rico – March 1, 2021 – Ring City USA begins its three-event residency in Puerto Rico this week when it takes over the Felix Pintor Gym in … More DANIELITO ZORILLA VS. RUSLAN MADIYEV HIGHLIGHTS THURSDAY’S PACKED RING CITY USA UNDERCARD