NEW YORK -- Thursday's rainout at Yankee Stadium gave Red Sox prospect Mike Shawaryn a little more time to reflect on the culmination of a dream come true -- being called up to the Major Leagues for the first time.

Shawaryn, Boston's No. 12 prospect according to MLB Pipeline, was selected from Triple-A Pawtucket to fill the roster spot vacated by righty Hector Velázquez, who went on the 10-day injured list with a lower back strain.

The New Jersey native should have a cheering section this weekend for a three-game rivalry showdown that will now start on Friday night.

"It was pretty special," Shawaryn said of getting the call. "I had to take a deep breath just to let it sink in. It's a dream come true. I called my girlfriend. She had work today, so I wanted to make sure she was good to go and then I called my parents. They're not too far away, so it's an easy drive for them."

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And, yes, the righty is aware of baseball's longest-standing rivalry. Who isn't?

"It's pretty cool," Shawaryn said. "I remember as a kid watching it on TV. So many awesome games and the rivalry is amazing, so to be able to be a part of it, and hopefully help the team win is always important."

The Red Sox drafted Shawaryn in the fifth round out of the University of Maryland in 2016.

While Shawaryn will initially give the Red Sox some bullpen depth, manager Alex Cora didn't rule out giving him a start at some point soon. With Nathan Eovaldi still on the injured list following right elbow surgery, the Red Sox have been piecing together the fifth spot in the rotation.

"We'll talk about it," said Cora. "Now with what's going on [with Thursday's rainout], where we're going, we'll sit down and see where we're at. We'll have a better answer by Saturday."

In 10 starts for Pawtucket this season, Shawaryn is 1-2 with a 3.72 ERA. Just one of Shawaryn's 68 appearances in professional baseball has come in relief.

Mookie-Benintendi flip-flop?

When Cora posted his lineup before the rainout, Mookie Betts was in the leadoff spot and Andrew Benintendi was batting second, reprising their roles from last season.

This season, Benintendi has primarily batted first with Betts in the No. 2 slot. Don't look for the switch back to 2018's order be permanent.

"No, [Mookie was] leading off because [J.A. Happ] is a lefty and Michael [Chavis] isn't playing," Cora said. "That wasn't the only reason, but [Benintendi] has been swinging the bat well, staying on pitches. He drove a few balls that he crushed that were outs to center field. He's in a good place."

Eovaldi to sim on Friday

Eovaldi will take another big step in his return from surgery when he throws a simulated game at Yankee Stadium on Friday.

There's no word yet on if Eovaldi will go on a Minor League rehab assignment before rejoining the rotation. If he does, it likely won't be an extended one.