Sources: Phils looking at Lee

The Phillies are intent on getting a front-line starting pitcher, whether they get Roy Halladay or not, and with the Indians' Cliff Lee seemingly lined up as the clear No. 2 choice for Philadelphia, officials with both teams are doing extensive background work on some minor leaguers who might be included in a trade, sources said on Tuesday.

The Indians' preference has been to get a major league-ready talent in return for Lee, in order to better position themselves to contend in 2010, and Kyle Drabek is the pitcher in the Phillies' organization who best fits that description. But the Phillies have been trying to make a Halladay deal without involving Drabek, and presumably, they'd be even more reluctant to trade Drabek for Lee.

The Indians, then, are evaluating the Phillies' farm system to see if they can fashion a deal with high-ceiling young talent -- which is why they're scouting Jason Knapp, a 6-foot-5, 240-pound pitcher who was the Phillies' second-round pick in 2008. Knapp was recently shut down because of shoulder fatigue, but he had shown enormous potential, striking out 111 in 85 1/3 innings while pitching in Class A and accumulating a 4.01 ERA.

One official familiar with the negotiations believes that the Phillies have enough high-end young pitching talent to build a deal for Lee without involving Drabek. The Indians are stocked with young position players but lack high-end pitching talent in their farm system.

A source told ESPN.com's Jayson Stark on Tuesday night that the Indians have been "very aggressive" in their discussions over Lee and Victor Martinez.

Lee, who turns 31 next month, is having another solid season for the Indians, posting a 3.14 ERA while walking just 33 in 152 innings. He will make $8 million in 2010 and then be eligible for free agency. While the Phillies are believed to be the leading suitor for Lee, the Red Sox have been after Martinez.

The Phillies' preference has been to trade for Halladay, and Philadelphia has always matched up well with the Jays in possibly arranging a package of players. But the Jays have insisted that Drabek and J.A. Happ be included in the trade, and the Phillies have said no; the two sides have remained at an impasse in their talks since Saturday.

Senior writer Buster Olney covers Major League Baseball for ESPN The Magazine.