The only New York Yankees in action Friday were those on the injured list.

While the big league club was rained out in Kansas City, Yankees pitcher James Paxton and shortstop Didi Gregorius continued testing out their injuries in extended spring training Friday – with mixed results.

Paxton still has discomfort in his ailing left knee, while Gregorius planned to start a minor league injury rehabilitation assignment Saturday that has him returning to the big league team by mid-June.

Paxton allowed one hit in four innings and struck out seven against Detroit. He has not pitched for the Yankees since May 3.

"I felt it a little bit, but I still was able to make my pitches, which is what I wanted to see," Paxton said.

Paxton had a cortisone shot May 4.

"If I come in tomorrow with more pain than I had walking in today, then we'll have to do something," Paxton added. "But, if I come in tomorrow and it feels the same as it did walking in today, then that's just how I'm going to have to pitch for right now."

Paxton threw 42 of 55 pitches for strikes.

"Tomorrow's a big day, because the stuff and the execution, all the things we wanted to see today, I think we saw. So now how does he bounce back?" Yankees manager Aaron Boone said. "I'm hoping tomorrow that he comes in and feels strong and we can start to move forward."

The 30-year-old left-hander, 3-2 with a 3.11 ERA in seven starts, is among five Yankees starting pitchers on the injured list, joined by ace Luis Severino (right shoulder inflammation), CC Sabathia (right knee inflammation), Jonathan Loaisiga (right shoulder strain) and Jordan Montgomery (Tommy John surgery).

Gregorius, coming back from Tommy John surgery last Oct. 17, was the designated hitter Friday in his fourth extended spring training game. He is scheduled to start a rehab assignment Saturday night with Class A Tampa. Position players can spent up to 20 days on a rehab assignment.

"My timing is not there yet," Gregorius said of his hitting. "But defensively I'm good. Arm and everything feels good."

Boone is eager to get his shortstop back.

"Obviously the kind of player he is, what he means to our team, between the lines and in the clubhouse and knowing all that he's gone through," Boone said. "But since the surgery, it's kind of gone how we've hoped every step of the way and this is another indication of that."

Shortstop Troy Tulowitzki got nine plate appearances in his first simulated game since reinjuring his left calf. He has not played the Yankees since April 3.

Tulowitzki could start a rehab assignment next week. He continued taking grounders at shortstop, third and second, where he worked on turning double plays.

Saturday twin bill

The Yankees and Royals will play a day-night doubleheader Saturday after a lousy forecast postponed Friday night's game.

"There's nothing you can do about it," said Royals manager Ned Yost, whose team has played just one day this week. "You can't fight the weather."

The first game is scheduled for 1:15 p.m. and Game 2 is set for 7:15 p.m. Thunderstorms are in the forecast the rest of the weekend, as well.

This is the third postponement in the four weeks and second in four days for the Royals. Kansas City's game Tuesday at St. Louis was postponed and made up the following day as a doubleheader. The Royals also had a game postponed April 30 against Tampa Bay. That game was also made up the following day.

The Yankees had the first two games of their series with Baltimore postponed on May 13 and 14. One game was made up May 15 and the other has been scheduled for Aug. 12.

Saturday's probables

RHP Jakob Junis (3-5), who was scheduled to start Friday night for Kansas City, will start Game 1 of the doubleheader. RHP Jorge Lopez (0-5) will start the nightcap. LHP Danny Duffy (3-1) was originally slated to start Saturday's game, but will start the series finale Sunday instead.

RHP Chad Green (0-2) was scheduled to be New York's opener Friday night and LHP J.A. Happ (3-3) was scheduled to throw Saturday for the Yankees, but no official announcement has been made by the team.