Jeff Roberson/AP

Sean Burnett’s worst outing of the season came in his first-ever postseason appearance in Game 2 of the National League Division Series on Monday. The left-handed reliever was tagged with three hits, one of them a home run, and four runs, three of them earned, while only notching two outs. His best pitch, his sharp, biting sinker that’s so capable of getting hitters to roll over them and ground out, was being smashed around the field.

Burnett, who struggled with effectiveness because of an irritated nerve in his throwing elbow, insists he is healthy. Everything was just off.

“It was just one of those days where it didn’t matter if I was facing a little league team or the St. Louis Cardinals, they were going to get a hit,” he said Tuesday after a team workout at Nationals Park. “Just didn’t have much. Just one of those days that’s hard to swallow but you go out there and give them your best shot. The balls weren’t moving. Everything I wanted it to do it wasn’t doing. You put it behind you.”

Said Nationals Manager Davey Johnson: “He just got the ball up, and I don’t know if it was lack of not being out there.  I thought his ball was pretty straight, usually has a nasty sinker.  His command wasn’t what it should be, but I got him out of there before he threw too many pitches so he’ll be available tomorrow.”

In late August and into early September, Burnett, who had Tommy John ligament replacement surgery in 2004, dealt with an irritated nerve in his left elbow. He was given 10 days off to rest and take anti-inflammatory medication and returned on Sept. 12. He refused an MRI exam because he was fearful of what it would show. (Burnett didn’t have any ligament damage then, he said, but his elbow issues could be revisited in the offseason.)

In his nine appearances to close the season after his return, he posted a 1.50 ERA in six innings. He has allowed only one earned run on eight hits, but opponents hit .308 off of him, 50 points higher than his season average to that point. On Monday, his first action in five days, the Cardinals pounced on Burnett, turning an 8-4 lead to 12-4.

“I feel great,” he said. “It was probably a week or so since I got off the mound yesterday. I was just off. It was just one of those where I didn’t have much. That was pretty easy to see. Everything was flat but I feel great. Fortunately it wasn’t a close game at the time. If you’re going to give them up, that’s the way to do it. Trying to be lights out every time you go out. It didn’t cost us too much and I got out there and got my feet wet and can get back in it.”