Rubby De La Rosa has impressed in Red Sox camp. (AP)

FORT MYERS, Fla. — The stuff is unquestionably major league-caliber.

Rubby De La Rosa showed an electrifying three-pitch mix on Friday against the Pirates, mixing a 94-96 mph fastball with a knee-buckling curve and a nasty, diving changeup at which opposing hitters waved helplessly. It was a three-pitch mix that screamed of top-of-the-rotation potential, the raw materials to be an impact starting pitcher in the big leagues.

The Sox, naturally, are enthused about that possibility. However, there’s a matter of timing regarding the 23-year-old.

After De La Rosa recorded his second straight outing of two scoreless innings (an appearance in which he struck out two and allowed a double), manager John Farrell was asked where De La Rosa will open the 2013 season. His only uncertainty pertained to which minor league level would prove appropriate for the prospect acquired from the Dodgers in last August’s blockbuster trade.

“He’ll be in the minor leagues in some place, whether that’s in Portland or in Pawtucket remains to be seen,” said Farrell. “I think the most important thing is he feels great physically. He’s been a student around [pitching coach Juan Nieves] and [special assistant to the GM Pedro Martinez]. He’s, as we said after the game in st. Louis, he’s a very good-looking young pitcher.”

Asked why De La Rosa couldn’t be a consideration for the major leagues, Farrell suggested that the team’s commitment to his deliberate progression — the Sox are limiting the right-hander to two innings in his spring outings, in deference to the fact that he’s coming off of Tommy John surgery and that he’s never thrown more than 110 innings in a year — and to the long-term view of him as a starter made him a near certainty for the minors.

Because De La Rosa won’t throw more than two innings in any spring outing, the only role in which he’d be considered for the big league roster at the start of the year would be the bullpen. And for now, that’s simply not an avenue that the Sox feel compelled to explore.

“We still want to start him. To put him in the bullpen, given what he’s come through …,” said Farrell, alluding to his surgery. “And our long-term view of him is currently as a starter. That doesn’t mean at some point in the future we wouldn’t look to make the most of the innings he’s gong to give on a given night if the need were to arise here. But our plan is to keep him at two innings through spring training and to build him up once the minor league season begins.”

That, in turn, means that Triple-A Pawtucket — where De La Rosa is almost certain to start the year — will benefit from a glimmering prospect in its rotation. De La Rosa seems likely to make an impact on the big league roster at some point in 2013, but it won’t be in the season’s earliest days.