Tua Tagovailoa is back. That’s good news for him and the Dolphins. The basic reality remains that he is returning to a sport where concussions are high on the list of possible injuries.

For a player who has suffered three (and probably four) concussions in less than two years – two of which triggered the fencing stance – it’s not a question of when, not if. And with the Dolphins having to miss an extended period of time after their last two games, it is crucial for the Dolphins to be prepared for the next game.

After his last one, they weren’t anymore. Only Tua can lead the offense. None of the substitutes were able to handle the timed distribution of the ball behind the line of scrimmage. Nobody managed to get the ball to Tyreek Hill consistently. Nobody could give the offense a kick in the ass.

Tua’s new contract is for a three-year commitment. The Dolphins need a high-end backup for the duration of this stretch. Really, as long as Tua is the team’s starting quarterback, the Dolphins will be crazy if they don’t have someone who can step in and go.

It’s unclear why they didn’t have someone ready to put up points and win games. Maybe they didn’t want Tua to feel threatened by a backup who could be almost as good as Tua.

If that were the case, these days must come to an end. You can’t tiptoe around Tua. They need a No. 2 who can be just as good as Tua because they have to assume they’re going to need that guy every play.

That’s not unfair to Tua. It reflects common sense.

The Dolphins haven’t been smart enough in the past. At this point, it would be the height of foolishness not to have a better backup plan for a quarterback who has a documented availability issue that could resurface at any time and without warning.