DENVER — On May 12 a year ago, Chris Iannetta dug deep into the box. He faced a 1-2 count and, having just seen a couple of curveballs, he guessed another was coming and told himself to stay back on the pitch.

But the veteran Rockies catcher guessed wrong, and he didn't have time to get out of the way of a 93 mph fastball that hit him in the face, knocking him to the dirt, blood pouring from his mouth and nose.

After that, it wasn't even a question. He would be wearing the C-Flap — a piece of plastic that attaches to the lower part of the helmet and extends to shield the cheek and jaw.

"Last year, I made one mistake in 11 years (by not turning my head) and it caused me to lose three teeth, get a boatload of stitches and have to cut an eighth of an inch of my lip off," said Iannetta, who was playing for Arizona at the time. "It's not worth running that risk."

Beyond the Colorado clubhouse, where Iannetta, outfielder Carlos Gonzalez and first baseman Ian Desmond are regulars who have adopted the C-Flap, the face protector is becoming popular across baseball. Flip on the TV to any major-league game, and you'll probably see at least a couple of players on each team wearing one, including some of the game's most visible stars such as the Angels' Mike Trout and the Yankees' Giancarlo Stanton.

"I think it's smart," Rockies pitcher Kyle Freeland said. "With how hard some guys throw — and with those guys, a lot of times not knowing if they're going to put it right in the zone or if a fastball will ride out inside — we've seen over the past few years more guys get hit up and in like Iannetta, Stanton and more. It's a smart step in the evolution of batter protection."

The occasional wildness of baseball's two hardest throwers, Cardinals rookie Jordan Hicks and Yankees veteran Aroldis Chapman, backs up Freeland's claim about high heat often coming with dangerous command.

Hicks has thrown Statcast's fastest pitch of 2018, 105.1 miles per hour, while Chapman has topped out at 103.3. Their average fastball velocities are 99.9 and 99.0, respectively. But the walk rates of both Hicks (5.18 per nine innings) and Chapman (4.23) rank in the bottom third among major-league relievers, and each pitcher has hit three batters this season. Those two are radar gun-busting outliers, but many pitchers seem to be throwing harder these days, with the amount of pitches that are 96-plus mph having more than tripled in a span of four years.

With pitches coming in faster than ever, the headgear has evolved.

The consensus in the Colorado clubhouse — even with those who don't yet use the C-Flap, such as Freeland and outfielder Noel Cuevas — is that the plastic extender will soon become the norm more than 30 years after its invention. It used to be used almost exclusively when a player was returning from facial injuries.

"It's a good move," Rockies manager Bud Black said. "The protection's come a long ways since there were guys when I came up who had the no-flap helmets — they were grandfathered in and didn't have to wear them. Because of the preventative aspect, I think you'll see more and more guys wear the C-Flap."

Cuevas said he likes the concept of the C-Flap and is likely going to start using it in the offseason. He wants time to adjust, although Iannetta said the C-Flap doesn't limit his vision.

"If I'm looking at the pitcher in my peripheral vision, I can see home plate and I can see way above the pitcher's head," Iannetta said. "So it doesn't block anything. I actually wish it was bigger."

Gonzalez, who began wearing the C-Flap after seeing the Cubs' Kris Bryant get drilled with a 96 mph heater from the Rockies' German Marquez on April 22, said he didn't have any issues adjusting to it and that the increased protection gives him peace of mind.

"The last time we played the Cubs and I saw Bryant get hit in the face, I spoke to him about it after, and he told me, 'I don't know why I waited until I got hit in the face to wear it,' " Gonzalez said. "That made a lot of sense, and I started wearing it right away."