Mitchell-Innes appeared in Somerset's opening five fixtures; including a pre-season friendly match against Glamorgan. During a season which the "Somerset County Herald" speculated would be "unpredictable" and lacking the "exaggerated optimism" of 1947, the county club lost all five matches in which Mitchell-Innes was captain. Mitchell-Innes scored 222 runs, including a solitary half-century, during a 10-wicket loss to Middlesex. After Denis Compton and Bill Edrich had scored 252 and 168 respectively, Mitchell-Innes was one of few Somerset players to bat with any confidence in the first-innings, scoring 65 runs. When Mitchell-Innes left the team for the Sudan, they were bottom of the County Championship with no points; they finished the season 12th of 17 after collecting 92 points, including five wins. Batting was identified as Somerset's weakest area in both 1947 and 1948; Mitchell-Innes' batting average of 22.20 placed him sixth in the county averages in 1948. The following year, Woodhouse took over as Somerset captain full-time. Mitchell-Innes was once again available for the first few weeks of the season, playing seven matches. He finished near the bottom of Somerset's batting averages, having scored 157 runs at 11.21; the second-lowest average of his career. It was his last season of first-class cricket, and he played his final match in May 1949 against Hampshire.