With the ballgame scoreless in the second inning, Alvarez caught Elvis Andrus' sinking liner and fired a perfect throw from right field to catcher Matt Wieters to easily get Adrian Beltre out at home.
"He has probably one of the best outfield arms I've ever seen," starter Kevin Gausman said of Alvarez, whom he saw plenty of in Triple-A Norfolk this year. "Obviously, that was huge. I don't think Beltre looked at the scouting report on the outfielders before the game. Yeah, he's definitely kind of a freak athlete."
Alvarez's contract was selected from Norfolk prior to the game. He was one of two additions on Friday, along with catcher Steve Clevenger, who returned from paternity leave. Henry Urrutia -- who was Alvarez's roommate in Norfolk -- was optioned to Triple-A to clear a roster spot.
And even though Alvarez, like many of his teammates, went hitless on Friday, he still left quite the impression.
"You don't get a whole lot of nerves about something you know you do real well. He's got a lot more than that. That was, 'I got you out pretty easy here. I don't need to really air it out here,'" manager Buck Showalter said of Alvarez's throw home. "He's got plenty of arm, and he doesn't have to overthrow it. That was impressive. That's a textbook throw."
Alvarez hit .275/.305/.424 with 24 doubles, two triples, 16 home runs, and 72 RBIs in 130 games with Norfolk this season. Named to the Triple-A All-Star team, he was a logical choice to come up given that Texas is starting three lefties in the weekend set.
"It was tough [offensively] early in the season," said Alvarez, with assistant hitting coach Einar Diaz serving as interpreter. "I never stopped working, got help from all the coaches over [at Triple-A], and it was a good thing I never gave up. Now I'm here."
Clevenger has hit .370 with four doubles, a home run and seven RBIs in 13 games this season, including five multihit efforts. He was placed on the paternity list on Tuesday, leaving after Monday's game in Kansas City.
"It's been awesome," Clevenger said of welcoming daughter Peyton Lee with his wife, Tiffany. "My family's very happy. I'm just glad everything went well. The doctors did a great job, and the nurses are taking great care of them. She's healthy, and my wife is doing great, and they're going to be home tomorrow."
Urrutia hit .265/.306/.382 with a double, a home run and six RBIs in 10 games this season.