Joe Burrow threw two touchdown passes for the Bengals, who claimed back-to-back wins to improve to 2-2, but the game will be remembered for Tagovailoa's injury where he was stretchered off and rushed to hospital with "head and neck injuries".
Tagovailoa went down during an eventful second quarter, slamming the back of his head into the turf in a Josh Tupou sack, where he appeared to suffer a seizure upon the initial contact. The Dolphins QB copped a heavy hit in last week's win over the Buffalo Bills but cleared protocols to play on despite fears of a concussion.
Teddy Bridgewater stepped in for Tagovailoa, shoveling a pass for Chase Edmonds' touchdown close to half-time to reduce the margin to 14-12 at long break, after Joe Mixon and Tee Higgins had earlier scored TDs for the Bengals.
Jason Sanders converted his third field goal of the game after Bridgewater combined with Tyreek Hill to have Miami up 15-14 at the final change, but the Bengals did all the scoring in the fourth quarter with Evan McPherson slotting two field goals before Burrow found a wide-open Hayden Hurst for a late TD after Vonn Bell's second pick.
Earlier, running back Mixon scored on the Bengals' opening drive while Edmonds dropped a Tagovailoa TD pass in the endzone, with Miami settling for a field goal. Both sides traded touchdowns in the second quarter after Tagovailoa's injury, with Burrow connecting with Higgins for a 59-yard TD deep down the left side, before Edmonds spun over for the Dolphins.
Burrow completed 20 of 31 attempts for 287 yards and two touchdowns with no interceptions, while Mixon had 24 carries for 61 yards. Higgins starred with 124 yards from seven receptions and Ja'Marr Chase made 81 from four receptions, including a Tyler Boyd 23-yard pass.
Tagovailoa made eight of 14 passes for 110 yards with one interception before being taken off, with Bridgewater completing 14 of 23 passes for 193 yards with one TD and an interception after stepping in. Wide receiver Hill had 160 yards on 10 receptions.