Nationals right-hander Stephen Strasburg reached a significant milestone in his rehab from Tommy John surgery Monday, throwing a simulated game. Strasburg had begun throwing to hitters during live practice, but a simulated game includes him sitting between simulated innings. "He's throwing good," general manager Mike Rizzo said. "His velocity is good. He's progressing. He's mixing in all his pitches, which is good. He's right on track where he needs to be." Rizzo declined to specify the speed on Strasburg's fastball, careful not to affect Strasburg's own expectations or effort level. "His velocity is good," Rizzo said. "I'll keep it at that." If he continues to progress at this rate, he could return to the Nationals by mid-September.