Washington easily nailed the first question, identifying Sabathia as the pitcher who won the most games (19) for the Yankees in 2009.
He also quickly buzzed in to answer that Yogi Berra once endorsed the beverage Yoo-Hoo, and before Leno could complete the next question, Washington rang in to announce the Yankees were previously known as the Highlanders.
"I've got no shot," Sabathia said, laughing.
Leno's next question concerned which Yankee was the MVP of the American League Championship Series last year.
Raising a finger, Sabathia said with a laugh, "That'd be me, Jay."
Sabathia whiffed on a multiple choice question of which Yankee struck out the most times in a single season, pointing a finger at Reggie Jackson. Washington rang in with Alfonso Soriano, the correct response (157 strikeouts in 2002).
"I know my Yankees, man," Washington said. "I know my Yankees."
Sabathia got in one final parting shot, identifying Mark Teixeira as the current Yankee who once played for Georgia Tech, the Rangers, Braves and Angels. But the final score came in as Washington 4, Sabathia 2.
"Have a good year, man," Washington told Sabathia. "See you in the spring."
Sabathia also appeared on Leno's show via satellite from New York's Rockefeller Center in November, shortly after the Yankees won the World Series.
In that segment, as part of a "10 Questions" exercise, Leno quizzed Sabathia on Phillies shortstop Jimmy Rollins' prediction that the Yankees would lose the World Series in five games.
"The trophy is where it belongs," Sabathia said then. "Me and Jimmy grew up together, we've known each other for a long time. But the trophy is definitely back in the right place."