Anxiety began to bubble here early Thursday evening, a right calf strain forcing Chase Headley to a second-inning exit. By the ninth, as Nationals Park drained on a school night and the Padres continued to play, the focus turned from uncertainty to frustration, a controversial technicality the culprit. In the 11th, an oddity reared its head in left field. There, Andrew Cashner, the pitcher himself, briefly cameoed. The cause: another injury, compounding the pain of it all. In a 4-3 victory that dragged the Padres through 12 costly innings, the Padres lost more than they won. They lost Headley to a second calf injury, the first having sidelined him for multiple weeks this spring. They lost a potential run that could have ended this game before more harm was inflicted, but Nationals manager Matt Williams’ challenge erased a stolen base in the ninth. In the 10th, the Padres lost another starter, Seth Smith, who strained his right groin chasing a double in the left-field corner. In the top of the 12th, Xavier Nady drove in Jedd Gyorko with what would prove a winning single. “It was a bizarre game,” said Nady, who entered in the ninth inning of a game that, figuratively and literally, exhausted the Padres’ roster. “A lot of strange happened.” None stranger than Cashner’s first-ever appearance somewhere other than the mound. With Smith out of the game and Tim Stauffer still on his - having thrown two scoreless innings of relief - Padres manager Bud Black opted to keep the long man in to face right-handed-hitter Jayson Werth, who was leading off the bottom of the 11th. Werth lined out to Stauffer, a couple hundred feet from where Cashner stood, and Black immediately enacted a double-switch, replacing Cashner with Tommy Medica and Stauffer with Alex Torres. The left-hander retired the next two batters to end the inning. “You’re trying to maximize your bullpen usage and you really have to do some things to try to win a game,” said Black, who noted that Torres had thrown two innings the night before.