KANSAS CITY, Mo. – Since the early days of spring training, Didi Gregorius has been lobbying for his quick return to the Yankees.“Didi thought he could be ready for opening day,’’ said Yankees manager Aaron Boone. “It doesn't surprise me.''On Saturday, Gregorius will graduate to an official rehab assignment with Class A Tampa. At this rate, the lefty-hitting shortstop could return by the week of June 10, if all goes well."This is another indication of this, another big step in working his way back,'' Boone said of Gregorius's accelerated pace. "It looks like it's going to be sooner rather than later.'' On Friday, Gregorius played in another extended spring training game."My timing is not there yet," Gregorius told the Associated Press in Tampa about his hitting. "But defensively I'm good. Arm and everything feels good."Gregorius has been rehabbing from Tommy John surgery last October to his right elbow.According to Boone, the plan is for Gregorius to play about two or three games at Class A Tampa before moving him up, possibly to Class AAA Scranton/Wilkes-Barre.“The good thing is, as he's worked his way back, he's been able to rack up a lot of at-bats between live at-bats, sim games, extended spring games,’’ Boone said of the shortstop’s ability to move quickly back to the Bronx.Back in lineup: Aaron Hicks still finding his timing as Yankees soar into first placeKnee ailing: Yankees' James Paxton throws four innings in rehab, still feeling discomfort“Now it's about getting the bounce-back, building him up to be able to play nine innings,’’ Boone said. “So far it's gone really well.’’According to Boone, “there’s a good chance’’ that Gregorius will require fewer than the max number of 20 rehab games allotted.