In the 2007–08 season, with Watford back in the Championship, Henderson scored thirteen league goals, including five in September. Two of these came in the last 10 minutes against Southampton, as, after coming on as a substitute, Henderson led Watford to victory. Henderson was named as the Championship Player of the Month for September. Henderson continued his good form until Christmas. Only three goals, however, came after the turn of the year. After being suspended for the first leg of the club's play-off semi-final against Hull City, Henderson returned to score the first goal in the second leg at the KC Stadium. However, Watford went on to lose the game 4–1, and 6–1 on aggregate. Henderson had been a highly popular player, and came third in the Player of the Season competition.