After missing the last four games with a concussion, Miami Dolphins quarterback Tua Tagovailoa will make his first start since Week 2 Sunday against the Arizona Cardinals.

The 26-year-old passed the NFL’s five-step return to participation protocol, was cleared to play by an independent neurological consultant, and gathered feedback from some of the top medical/neurological experts who all believe it’s safe for him to resume his career.

But after the announcement of Tagovailoa’s return was made by head coach Mike McDaniel on Friday, fans were all saying the same thing: Tagovailoa really should be wearing a Guardian Cap if he insists on playing again.

It may seem foolish for Tagovailoa not to wear a Guardian Cap given the rave reviews the NFL has given the equipment for reducing the number of concussions league-wide. However, NFL chief medical doctor Allen Sills says there’s actually a good reason Tagovailoa is choosing not to wear one.

“For most helmets adding a Guardian Cap — an extra layer of padding — will reduce the force of each blow by somewhere between 10 and 15%,” Sills told CBS Sports. “Now there is a subset of helmets that we tagged as Guardian Cap optional.

“And the reason for that was that those helmets in the laboratory testing showed that there really was not additional benefit of that magnitude by adding a Guardian Cap. In other words, the helmet itself was doing as good a job of mitigating the force as a regular helmet plus a guardian cap. So adding a Guardian Cap to those helmets did not show that same 10 to 15% benefit.”

Tagovailoa’s Vicis Zero2 Matrix ID QB helmet is one of the ones that the data shows makes no difference whether a Guardian Cap or worn or not because it already has additional padding to lessen any possible blows to the head.

Adding a Guardian Cap to a player’s helmet adds approximately one pound of weight, and many passers prefer having a lighter helmet given how much they have to scan the field and move their head during plays.