Seattle Mariners ace
is likely to miss two to three starts with a strained muscle in his right elbow.
Mariners medical director Ed Khalfayan said yesterday that the 21-year-old righthander would not throw for five days.
Hernandez (2-1, 1.56 ERA) left his start Wednesday against Minnesota after just a third of an inning.
Randy Johnson gave up two runs in six innings in a minor-league start, most likely his final tune-up before joining the Arizona Diamondbacks.
The 43-year-old lefthander, who had back surgery in October, allowed six hits, walked one and struck out seven for triple-A Tucson against Salt Lake.
Righthander Rodrigo Lopez (elbow tightness) was put on the 15-day disabled list by the Colorado Rockies, who filled his roster spot by purchasing the contract of righthander Matt Herges from triple-A Colorado Springs.
Los Angeles Angels second baseman Howie Kendrick was placed on the 15-day disabled list after breaking his left hand.
Oakland's Chad Gaudin hit Kendrick with a pitch Tuesday during the Athletics' 4-1 victory. The 23-year-old Kendrick is hitting .327 with two homers and four RBIs.
The Angels said slugger Vladimir Guerrero, hit on the right wrist by Boston's Josh Beckett on Monday, might return to the lineup as early as tonight. Guerrero is hitting .364 with three homers and 12 RBIs.
The San Diego Padres recalled lefthander Justin Hampson from triple-A Portland and optioning Mike Thompson to the Beavers.
Torii Hunter remained out of the Minnesota Twins' starting lineup against Seattle because of a bruised left shoulder.
Hunter was hurt Tuesday while trying to make a tumbling catch of a sinking line drive hit by Jose Vidro.
The Texas Rangers and Red Sox swapped minor-league pitchers, with lefthander Daniel Haigwood going to Boston for righthander Scott Shoemaker and cash.
Haigwood was acquired by Texas from the Phillies in a trade last year.
The Cincinnati Reds unveiled a jersey above the home bullpen last night in memory of former pitching coach Vern Ruhle, who died Jan. 20 of multiple myeloma.