By Bruce Levine–

GLENDALE, Ariz. (CBS) — It may not be headline news given that no trade has taken place yet, but the demand for White Sox left-hander Jose Quintana appears to be as robust as ever a couple weeks into spring training.

The Astros, Cardinals, Pirates and Yankees are teams believed to be dug into the sweepstakes for the 28-year-old Quintana, who’s on the trade block as the White Sox have embarked on a rebuild. The White Sox’s focus in a potential Quintana trade is the quality of prospects they get in return, not the quantity, sources said.

“As we sit here right now, it’s more a function of continuing on the conversations we have had,” White Sox general manager Rick Hahn said earlier in the week. “We will see if we can build off of those.”

Quintana made his first start of the spring Sunday, and there were a dozen scouts in attendance to watch him. Quintana allowed one run on a solo homer and struck out two in two innings of work as the White Sox beat the Rockies, 7-3. He was sharp in his limited work, with one mistake on a breaking ball that resulted in a Chris Valaika homer.

“For the first day, I felt I had good stuff,” Quintana said. “A couple pitches I spun up there. Overall I felt good.”

Quintana is expected to make one more start for Chicago in spring training before heading to the World Baseball Classic on or around March 5 to play for his native Colombia. The rules will limited the number of pitches any big league pitcher can throw.

Quintana offers interested suitors consistent top-of-the-rotation pitching. He has recorded four straight seasons of 200-plus innings and sports a career 3.41 ERA. For several seasons, he has been arguably the best under-the-radar pitchers in the game.

Another large part of Quintana’s allure is his contract control. He’s under team control for four more seasons at about $38 million. Essentially, that $9.5 million annual average salary is half of what most top-of-the-rotation pitchers are worth.

Quintana is also highly regarded in the locker room as a favorite of his teammates, having impressed others by working hard to master English and always showing support.

Bruce Levine covers the Cubs and White Sox for 670 The Score and CBSChicago.com. Follow him on Twitter @MLBBruceLevine.