PEORIA, Ariz. — This is one unusual experiment for Cliff Lee and the Seattle Mariners. Any major league team, for that matter.

Lee is sidelined with a strained abdomen that could cause him to miss the first weeks of the season, but the Mariners are using platelet-rich plasma injection therapy to treat their prized winter acquisition.

The treatment for the 2008 AL Cy Young Award winner has been used for the last decade mainly on joint issues such as tennis elbow, hamstring strains or other injuries to limbs.

Not on abdomens. That makes Lee something of a medical experiment.

"I guess you'd have to say that," Mariners medical director Dr. Ed Khalfayan said yesterday in a telephone interview from his home in the Seattle area.

Khalfayan gave the 31-year-old left-hander an ultrasound and the platelet-rich plasma therapy on March 19 in Seattle, injecting Lee's own blood into the injured area to focus its healing powers on his ailing midsection.

Khalfayan doesn't like the negative connotation that comes with the term "experimental." But he agrees what the Mariners are doing with Lee remains largely unproven.

"It hasn't gotten to the point that it's accepted, standard practice," Khalfayan said of the therapy.

He said the only risk is a small one of infection, as with any injection, and is far less than the risk of injecting drugs such as cortisone.

Lee said he felt markedly better three days after the injection, but he had pain throwing for five minutes on flat ground on Tuesday and Thursday. He won't throw again until at least Wednesday, making it likely he will begin the season on the disabled list.

This is Lee's third strained abdominal muscle since 2003. The other two injuries also happened in spring training when he was with Cleveland and put Lee out for at least six weeks.

The Mariners are hoping this new idea reduces that recovery time.

RANGERS

FELDMAN TABBED ACE

The Texas Rangers have selected Scott Feldman as their opening day starter, completing the right-hander's ascent from extra arm to staff ace.

The team made the announcement yesterday, a year after he started the season in the bullpen. He went on to join the rotation and lead the team in wins.

The 27-year-old was 17-8 with a 4.08 ERA in 31 starts and 34 overall appearances last season.

Feldman will be joined in the rotation by Rich Harden, Colby Lewis, Matt Harrison and one-time closer C.J. Wilson.

Meanwhile, the Rangers have acquired second baseman Andres Blanco from the Chicago Cubs for a player to be named or cash. The deal was announced yesterday.

TWINS

TARGET FIELD OPENS

Target Field is open for business.

The University of Minnesota lost to Louisiana Tech, 9-1, yesterday, the first baseball game played at the Minnesota Twins' new home.

More than 36,000 people came through the turnstiles after they opened in the morning for fans to take a look, sit in the seats and sample the food. Tickets were $2, with proceeds going to the team's community fund. Former Gophers and Twins catcher Terry Steinbach threw out the ceremonial first pitch.

The Twins' home opener is on April 12, and they have a pair of exhibition games next week.

AND WHAT'S MORE ...

Dodgers reliever Ronald Belisario finally resolved his visa problems in his native Venezuela and is expected to report to spring training today. ... Baseball commissioner Bud Selig said yesterday there will be no "Cubs tax," the controversial proposal that would have placed a surcharge on tickets sold at all Arizona spring games to pay for a new ballpark for the Chicago Cubs in Mesa. ... Jacque Jones has been told by manager Ron Gardnehire that he will not make the Minnesota Twins' opening day roster.