MESA, Ariz. — Left-hander Justin Steele was scheduled to start Thursday evening against the Royals, but the Cubs decided to scratch him from the starting lineup when he came down with what they called flulike symptoms. Right-hander Ben Brown got the start instead.

The decision came down to allowing Steele to recover and to keep him from spreading the illness to his teammates, bench coach Ryan Flaherty said.

‘‘It shouldn’t change his outcome for his status in Japan, for sure,’’ Flaherty said.

Steele is expected to pitch once more before the Cubs leave Tuesday for Tokyo, bringing his total to three spring starts. He built up to about 55 pitches in his last start between the game and a bullpen session afterward.

Because the Tokyo Series on March 18-19 against the Dodgers pushes up the start of the regular season, the Cubs weren’t expecting their starters to be fully stretched out. Steele is scheduled to pitch the second game of that series.

‘Spring Breakout’ roster announced

Cubs prospects will play in two ‘‘Spring Breakout’’ games while the major-league team is in Japan. The first is against the Dodgers’ prospects Thursday at Camelback Ranch in Glendale and the second against the Angels’ prospects March 15 at Sloan Park.

MLB announced the rosters Thursday, and the Cubs’ squad for the first game is headlined by three top-100 prospects, as ranked by MLB Pipeline: right-hander Cade Horton (No. 51), catcher Moises Ballesteros (No. 68) and infielder James Triantos (No. 72).

Injury update

Right-hander Javier Assad is scheduled to throw his first bullpen session Saturday since straining his left oblique before the official start of spring training. The Cubs already had ruled him out for the start of the season.

Royals 9, Cubs 3

Ben Brown made his second spring start Thursday, pitching 3 2/3 innings. He allowed three runs, but none until the fourth. Brown has been working on his changeup and estimated he threw at least six or seven, a personal record.

• Seiya Suzuki was the only Cubs player with a hit in the first four innings. In the fifth, Pete Crow-Armstrong lined a single to center and scored the Cubs’ first run on a wild pitch.

• Kyle Tucker still is looking for his first spring hit with the Cubs. He has gone 0-for-17 with three walks.

• On deck: Cubs at White Sox, 2:05 p.m. Friday, Glendale, 670-AM, Colin Rea vs. Shane Smith.