Apple (AAPL) is deepening its push into sports, adding its Apple Watch to the list of its products that can be found in and around major league teams.

The tech giant and the NHL announced on Friday that referees have been using the Apple Watch throughout the current season as a means of monitoring the game without having to take their eyes off of the action on the ice.

The new system includes an Apple Watch Series model or Apple Watch Ultra and a specialized app that provides the refs with data like the game clock, a countdown to the end of a period, and a notification letting them know when a player is coming out of the penalty box.

“Being able to provide the official the game clock on the wrist so [the referees aren’t] looking up, trying to find the scoreboard when [they’re] skating … was really important to make sure there’s focus on the ice and the players and the play,” said Andres de Corral, vice president of digital services at Presidio, the company behind the app.

To ensure the refs aren’t dependent on looking at their watches, Presidio’s app provides haptic feedback patterns that vibrate for end-of-period and penalty box alerts.

“So notifying the official, ‘10 … 3, 2, 1, there’s a 200-pound person that’s about to exit a penalty box flying at you … Careful,’” Corral said.