NEW YORK -- The Boston Red Sox promoted highly touted prospect Mookie Betts from the minors Saturday, hoping he might be able to boost a lineup that's had trouble scoring runs all season.
The sagging World Series champions selected the contract of the 21-year-old outfielder from Pawtucket and sent promising right-hander Rubby De La Rosa to their top farm club.
Betts wasn't in the lineup against New York ace Masahiro Tanaka on Saturday night. But Red Sox manager John Farrell said he anticipated Betts would start and make his major league debut Sunday night at Yankee Stadium.
"He isn't looked on as the savior for the Red Sox," Farrell said.
But Boston certainly needs some kind of spark. The Red Sox went into the game with a 36-44 record and ranked 13th among the 15 AL teams in runs.
"We have to get better," general manager Ben Cherington said.
The Red Sox started the day eight games behind AL East-leading Toronto.
"We think that's a deficit we can manage," Cherington said, adding, "we got to get going."
Farrell said Betts would play in center field and right field. That Betts was even here this summer was a surprise considering he wasn't really on the Red Sox radar in spring training, having never been above Class A.
"It's a quick ascent, no doubt about it," Farrell said.
He said: "Players tell you when the time has come. The time has come, as has Mookie," he said.
Betts was hitting a combined .345 at Triple-A and Double-A this season with eight home runs and 29 steals. He scored 70 runs and had 48 RBIs in 77 games, and had been picked to play in the All-Star Futures Game next month in Minnesota.
Betts had a .437 on-base percentage and a .520 slugging average.
A fifth-round draft pick in 2011, Betts was a middle infielder before splitting time in the outfield this season. The right-handed hitter safely reached base in 71 straight games over two seasons in the regular season and playoffs before the streak ended in May.
"He outpaced some of the projections," Farrell said.
Farrell and Cherington said they wanted to give Betts a day to get acclimated to life in the majors before putting him into the lineup. On Saturday night, Daniel Nava started in left field, Jackie Bradley Jr. was in center and Brock Holt was in right.
The Red Sox had hoped star outfielder Shane Victorino would've rejoined them by now, but his rehabilitation for an injured hamstring has been shut down and there's no timetable for his return.
"We still believe he's going to play and help us, but obviously there was a setback this week," Cherington said.
The 25-year-old De La Rosa went 2-2 with a 2.51 ERA in five starts for the Red Sox. Recalled from the minors on May 31, he was a bright spot for Boston.
Farrell said he didn't have a slot for De La Rosa's next start and, with Boston carrying 13 pitchers and only 12 position players, it made sense to option De La Rosa to Pawtucket.
Cherington said was confident De La Rosa would be back in the majors at some point.
The Red Sox got De La Rosa on Aug. 25, 2012, as part of a nine-player trade with the Los Angeles Dodgers that involved Adrian Gonzalez, Carl Crawford and Josh Beckett.