Red Sox shortstop Jed Lowrie has been diagnosed with mononucleosis. "He can play as tolerated," manager Terry Francona said. "He was on the bike yesterday. I don't think he'll feel like he has a ton of energy for the next week or two, but he can do physical things as tolerated. "So we'll monitor him. We'll keep an eye on him, and monitor him. That's about the best we can do." Lowrie first complained of fatigue a week ago.