Another Nationals loss, this one an 8-3 defeat against the Los Angeles Angels of Anaheim. But the big news out of this one is that Shawn Hill will receive another opinion from the Mayo Clinic in Rochester, Minn., on the forearm pain that’s been plaguing him all season and will likely go on the disabled list. Hill gave up eight runs (six earned) in three innings tonight, five days after going 3 2/3 innings against Minnesota. The big problem has been that the forearm pain has made his delivery, which allows him to naturally sink the ball, less effective. I’ll stop there, and let the always-engaging Randy St. Claire explain what’s going on. On what makes a sinkerballer effective: If you watch Brandon Webb, or (Jeff) Weaver, or any of these guys, when they throw their sinker, their hand will go wham, like that, over the top of the ball. Hes not able to do that upon his finish. He does it naturally. He just throws his fastball and he naturally pronates it. Hes always been a sinkerball guy. (A quick definition: Pronation is the rotation a pitcher puts on the ball with his forearm, in this case the method by which Hill can naturally make the ball drop. So you can imagine how debilitating this type of injury is to a pitcher like Hill.) On what the pain is doing to Hill’s delivery: Hes not able to get over the top of the ball the way he does normally. The ball doesnt have the same sink and movement that it normally does. Its kind of a flatter trajectory. Its elevating in the zone a little bit, and hes getting the ball up. On the different ways Hill has tried to cope with the pain: Right from the beginning, they say he cant hurt himself, that hes going to try to work through the pain. Hes tried not doing sides. He did a side the other day, the one before he skipped, and he did two before that. But those are the only ones hes done. I dont even know if its the work. Hes not able to do what he needs to do in his delivery, naturally, which is that pronation. Hes always had that. He does that naturally, and hes not able to do that. In other news: Paul Lo Duca underwent a CT scan and blood tests at Sibley Hospital after coming out of the game with light-headedness in the second inning. Manny Acta said he was released from the hospital after receiving intravenous fluid. Series finale is here tomorrow at 7:10 p.m. Pretty decent pitching matchup, too. Tim Redding (6-3, 4.12 ERA) faces Angels ace Ervin Santana (9-3, 3.17).