What’s happening? – Miguel Castro makes his first Grapefruit League start today when the Orioles face the Toronto Blue Jays in Dunedin, Fla. Castro is battling with Nestor Cortes Jr., and Mike Wright Jr., for the fifth spot in the Orioles’ rotation.

Castro, who was scratched from his scheduled start Feb. 25 due to tendinitis in his knees and a sore lower back, worked two innings against Pittsburgh in a “B” game March 2.

He’s in the mix for the rotation, but also could end up in the bullpen, where he excelled for the Orioles throughout much of 2017. Today will be the first time Castro’s pitching line will “count” in spring training statistics.

** The Orioles suddenly have become a little thin at first base – for now.

Mark Trumbo has a right quad injury, and he’s expected to miss up to a week, manager Buck Showalter said. Trumbo had felt some tightness previously, but aggravated the quad in Tuesday’s game at Fort Myers.

Chris Davis’ sore right elbow continues to progress, Showalter said, but he’s not ready to play.

Because Trumbo and Davis are both out, Trey Mancini started at first base Thursday. Pedro Alvarez, who was the DH, can also play first, as can recently signed Danny Valencia. Garabez Rosa, who was reassigned to minor league camp Sunday, returned Thursday and played first after Mancini left the game.

** Gabriel Ynoa, who is scheduled for a Saturday start, was sent for an MRI because he’s complaining of shin splints.

** Chris Tillman, who has yet to be scheduled for a Grapefruit League start, threw 61 pitches in three innings of a simulated game on the back field at the Ed Smith Stadium complex Thursday.

What’s happened? – Cortes allowed three runs on six hits in three innings in the Orioles’ 9-3 loss to Toronto on Thursday. In three Grapefruit League starts, Cortes has allowed five runs on 11 hits in seven innings for a 6.43 ERA.

“I wasn’t making them hit my pitch and I think that’s what hurt me today,” Cortes said. “Too many pitches left over the plate and too many strikes.”

Showalter has just a few weeks to make a decision on whether to keep the left-handed Rule 5 draft pick.

“You’ve got to be careful about putting too much [emphasis on] spring training, but where he’s concerned that’s kind of what you’re going by,” Showalter said.

Darren O’Day pitched a snappy 1-2-3 inning in the fourth, the only spotless inning for the Orioles.

Mychal Givens allowed two runs, one of them unearned, in the fifth.

** The Orioles reassigned right-handed pitcher Perci Garner to minor league camp. Garner had thrown three perfect innings.

Garner’s departure leaves 51 players in camp, and Showalter said that there would be a few more cuts this morning.

What’s up with? – Joely Rodriguez. One of the main contenders for the situational left-hander’s job, Rodriguez, who was signed to a minor league contract last Nov. 28, has a 1-2 record with 5.40 ERA in 38 games with the Phillies in 2016 and 2017.

This spring, Rodriguez has allowed four hits in 4 1/3 scoreless innings.

“When you look at the track record, and see what you’re seeing here, they’re two different things,” Showalter said. “He’s 26, he’s pitched a lot of baseball. What you’re seeing here so far, it doesn’t really fit the track record.”

What’s what? – Tim Beckham committed his first error of the spring in his ninth game at third base. Toronto’s Jason Leblebijian’s grounder bounced off Beckham’s glove and found its way to Manny Machado. Machado’s throw to first was not in time.

What’s the word? – “I want (him) to, because that’s the way it is up here. This isn’t Instructional League. This is the major leagues, and you’re trying to take people that can help you win baseball games.” — Buck Showalter on whether Cortes realizes he has to impress with each outing.

What’s the number? – 2.That’s how many sons of former Orioles played in Thursday’s game for the Blue Jays. Highly touted prospect Vladimir Guerrero, Jr. had four hits as the designated hitter.

The younger Guerrero, whose father was with the Orioles in 2011, and was elected to the Hall of Fame in January, has yet to play above Class A.

Dwight Smith, Jr., whose father played 28 games for the Orioles in 1994, was hitless in one at-bat.

Toronto’s lineup Thursday featured another son of a former big leaguer. Bo Bichette, whose father, Dante, hit 274 home runs in an excellent big league career, had two hits and drove in two runs. Unlike his father, who was an outfielder, Bo Bichette is a highly regarded shortstop.

What’s the record? — 6-7-1. The Orioles again face Toronto today, but this time they’ll go to Dunedin Stadium. Castro’s opponent will be Marco Estrada.