OAKLAND -- It has been 439 days since Brett Anderson last pitched in a Major League game after undergoing Tommy John surgery in 2011. The wait could soon be over. Anderson threw a 40-pitch bullpen session on Saturday in front of A's manager Bob Melvin and pitching coach Curt Young. By all accounts it is fair to say the results exceeded all expectations. "It looked like he stepped on it a little harder," Melvin said. "We've seen him throw bullpens in the past and he's really got good stuff." Anderson struck out a season-high seven batters in his most recent start on Wednesday. The A's have a tough decision to make -- reinstate Anderson in time for his next outing, or let him throw more in Triple-A. "We'll have a decision at some point soon," Melvin said. "We will find a way to get him in there at some point. He is that good. We just have to find the right timing for it."Melvin noted that the determination as to who will leave the rotation to make room for Anderson has to do with who is pitching well at the time, and potential match ups with other teams. Anderson feels like he is close to ready. The light at the end of the tunnel might be so bright that it is blinding. "I'm just excited to be pitching in a big league game eventually," Anderson said. "Whether it be this time or after another start, or whatever it may be. I'm just looking forward to be pitching for the A's again at some point." Anderson says his velocity has been up to 94-mph and feels confident he is ready to get people out at the big league level. He doesn't think anything in particular mechanically led to the injury, but noted that he wants to try and limit his breaking balls a bit. That being said, his most important pitch is his slider. Finding that pitch is the key to his success. After his last start he feels it is nearly back to full strength. "I struck out seven and probably five or six of them were on sliders," Anderson said of his previous outing. "It's getting back to where I like it, and can use it in different situations for strikeouts or for ground balls. It's coming around." Anderson said that his most important bullpen was the first one he threw after Tommy John surgery, but couldn't recall another side session that was as important. How he performed on the mound Saturday could play a key role in how soon he will return to the Oakland starting rotation."I felt like it was good. Hopefully they did too," Anderson said. "Guys have been throwing well so there's only so many spots in the rotation. We'll see what happens."