WASHINGTON -- No one was forecasting Johan Santana will be shut down for the season after Friday's latest subpar start. But pitching coach Dan Warthen indicated at the very least that team brass would need to have a "powwow" to discuss the topic. And Santana, rather than be dismissive of that as an option, seemed receptive to halting his season before the end of September if a meeting of minds arrives at that decision.

Santana on Friday became the first pitcher in franchise history to allow six or more earned runs in five straight starts. He insisted his surgically repaired left shoulder is healthy, and assigned the latest damage to bad pitch location on homers to Michael Morse and Bryce Harper.

"You know, my season has been a roller coaster," Santana said after being charged with six runs in five innings as his ERA swelled to 8.27 in 10 starts since his June 1 no-hitter. "A lot of ups and downs. Good days. Bad days. But I'm very positive about everything, because I'm coming back from a major surgery, and I've been able to be out there every five games. ... Right now my shoulder is fine. I don't have any issues with it. It's just that it has been a long season for me."

Would Santana resist if team brass felt it was beneficial to cut short his season to ensure maximum health for 2013? (Santana is due to make $31 million next year, including the buyout of the following season.)

"This is a decision, whatever it will be, it's going to be together. It's not going to be based on me or them," Santana said. "I think it has to be in a way where we'll talk together and see how we feel. Whatever they want to do, as long as it works out for everybody in the long term, I think it will be fine."

Said Warthen about a potential shutdown: "We'll have to talk about that, and we'll have to talk to Johan and see how the body feels, how the arm feels, how he feels mentally. I'm not going to discount anything. I'm not going to say one way or the other. We'll all sit down and have a powwow, I would imagine as soon as we get home and see Sandy [Alderson] and make the discussion and then talk to Johan and see how the back is and everything else -- see how sore he is."

Santana began throwing last offseason on Dec. 15, six weeks earlier than normal, as part of his rehab program, so he may now be gassed. And Santana only had one three-inning rehab assignment with Brooklyn before returning from the DL. He then tossed only 43 pitches in last weekend's start against the Braves. So Santana's pitch count may not be built up enough to have prolonged success in a game just yet.

Sure enough, Santana retired the first nine Nationals on Friday. His outing unraveled, Warthen noted, about the 50-pitch mark.

"I was so encouraged with the outing tonight, outside of the score and us losing -- the first three innings of being perfect baseball," Warthen said. "And we're seeing a strong, solid average fastball, getting the ball to the zone where he wanted it. It's very obvious in the fourth and fifth inning that the ball was leaking back over the plate, losing velocity. It's just a matter of building that arm strength back up, because we saw vintage Johan for three innings."

Said Santana: "I've been throwing baseballs since Dec. 15. That's when my workouts started, aiming for spring training and Opening Day. And there were a lot of question marks if I was going to break camp with the team. And I made the team and I started the first game of the season. So it has been a long, long season for me -- but at the same time very positive, because even though I had rough outings, I still worked through them and I'm able to go back out there and do my thing. Sometimes mechanically you're not there. Or your command is not there. So that's something you have to work on. Physically, up to this point, I feel that I've done a lot and without any problems."