After the perfect game, he seemed to suddenly lose effectiveness. It was the last shutout he would throw in his career. In 2000, he posted the worst record of his career, 4–14, while seeing his ERA balloon to 6.91, more than double his mark the previous year. In spite of his ineffectiveness, Cone was brought in during game four of the 2000 World Series to face the Mets' Mike Piazza, a controversial decision at the time — Denny Neagle had given up a home run to Piazza in his previous at-bat, but was pitching with a lead and only needed to retire Piazza to go the minimum five innings to be eligible for a win. Cone induced a pop-up to end the inning. It was the only batter he faced in the entire Series.