Dodgers fans enamored with reliever Brusdar Graterol and his triple-digit fastball have only scratched the surface of what the 21-year-old rookie has brought to the Dodgers.

Let manager Dave Roberts pull back the curtain a little on what Graterol brings when he’s not on the mound.

“We didn’t know a lot about Brusdar,” said Roberts. “The one thing I see, he shags three groups a day. For a reliever, to just be out there and just be grateful he’s a big league ballplayer out on a big league field running balls down, serving his teammates, I love seeing that.

“He’s got this crazy big truck that he used to honk the horn when he would leave Summer Camp, and we would all know he was leaving. He’s in the ‘pen and he’s sort of like a cheerleader. When a guy hits a home run or makes a great play, he’s like re-enacting it. Guys have really gravitated toward him. So I think for me, it’s just that youthful enthusiasm component that’s certainly refreshing.”

Graterol came to the Dodgers in the unusual trade that sent Kenta Maeda (with the Dodgers paying his $10 million salary) and Minor Leaguer Jair Camargo to the Twins for Graterol and outfielder Luke Raley, after Graterol failed a Red Sox physical that nixed a trade to Boston in the original Mookie Betts deal.

In 10 appearances with the Dodgers, Graterol has allowed four runs in 9 2/3 innings, with seven strikeouts, one walk and no homers. Graterol’s sinker is averaging 98.9 mph and he’s throwing it more this year than he did last year. While his strikeout percentage is down slightly from last year (25% to 20%), his walk percentage is down significantly (5.0% to 2.9%).

• Roberts said Edwin Ríos (hamstring) is making steady progress in his rehab at the club’s alternate training site and is on track to return on or close to his eligible date to return of next Thursday.