Robert Deutsch-USA TODAY

Heading into the 2013 season, Koji Uehara was a career middle reliever who the Boston Red Sox hoped could help bridge the seventh or eighth inning for Joel Hanrahan. Now, he's the American League Championship Series MVP.

The Red Sox closer was named the MVP on Saturday night, just moments after he closed the door on the Detroit Tigers to send Boston to the World Series. Uehara pitched a scoreless ninth inning, striking out two Tigers batters while only giving up only an infield single to Austin Jackson, as the Red Sox won 5-2 thanks to a Shane Victorino grand slam in the seventh inning.

The 38-year-old righty pitched in five of the series' six games, holding Detroit scoreless and giving up only four hits. He recorded saves in three of Boston's four wins, becoming the first reliever since Mariano Rivera in 2003 to win an LCS MVP award.

Over eight appearances this postseason overall, Uehara has given up just one run and converted all five of his save chances over nine innings of work. While he's made it look easy throughout the postseason, he told Fox Sports' Erin Andrews that there were definitely nerves heading onto the mound.

"I almost threw up," Uehara said through a translator.

Uehara's journey to this triumph is as unlikely as any. He signed a two-year deal with Boston last winter after splitting four seasons with the Baltimore Orioles and Texas Rangers, performing well but unspectacularly. After season-ending injuries to Hanrahan and Andrew Bailey, he took over as the full-time closer late in June.

Since assuming the ninth-inning role, Uehara has been spectacular. Mark Simon of ESPN Stats & Info pointed out just how unhittable he's been since the beginning of July:

The Red Sox will now advance to the World Series to take on the St. Louis Cardinals, who finished off the Los Angeles Dodgers on Friday night. While St. Louis matched Boston's MLB-best 97-65 regular-season record and will prove a tough challenge, the Cardinals better hope not too many games come down to the ninth inning.

If they do, the Tigers found out the hard way what will probably happen.

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