Could Xavier Cedeno overtake Jerry Blevins for a playoff roster spot?

When discussing left-handed relievers, are Jerry Blevins and Xavier Cedeno battling for one playoff roster spot? Should they be? Blevins has been with the team the whole season. He started off well. But recently, he has had some rough outings, especially the Sept. 10 appearance against the Braves at Nationals Park. Blevins allowed three earned runs on two hits and a walk in just one-third of an inning. The Nationals lost that game 6-2. They lost only two of the next 11 games. Blevins has bounced back his last two outings. He has allowed no runs and no hits with five strikeouts in two innings since, on Sept. 12 and 17. His ERA is 5.17 on the season and 5.91 the last 10 games. He has made 61 appearances. His ERA against left-handers is 2.70, but his ERA against right-handers is 8.25. Cedeno made a big splash against the Dodgers on the road Sept. 2 and 3. He threw a scoreless inning, showing aggressive stuff in that first game, and then had a huge strikeout of Adrian Gonzalez in a high-leverage situation in the 10th inning when the Nationals eventually came back to win 8-5 in 14 innings. He has since made two other appearances, allowing one earned run against the Phillies in one of those outings. He hasn't pitched in a game since Sept. 13, when he struck out two in a scoreless appearance at the Mets. He has appeared in seven games with the Nats this season, but shined at Triple-A Syracuse. With the Chiefs, Cedeno went 5-1 with a 2.29 ERA and four saves in 35 games. They have each had only two appearances since early September. Blevins has had two games since Sept. 10. Cedeno has had only two appearances since Sept. 3. It does not seem to be enough to lift Cedeno past Blevins for the final left-handed relief spot on the playoff roster. It appears Cedeno's stuff is more swing-and-miss, which is exciting to watch. But Blevins has been with the team the entire campaign, and has more experience. Christian Garcia was able to grab a roster spot in the 2012 postseason after a nice end to the season when he displayed a 95 mph velocity. Is Cedeno in that same realm? Just because they haven't used Cedeno that much in September, it appears Blevins will be OK. Either way, Cedeno appears to have a good shot at getting a roster spot in the future, if he could only get a few more calls.