The Oxford cricket historian Geoffrey Bolton describes the next two years as being "full of disappointment" for Oxford. Partially indicative of this, Mitchell-Innes once again topped the batting averages, and led all Oxford batsmen in terms of runs scored, but his figures were in stark contrast to the previous year: he averaged 38.70 for his 774 runs. He hit centuries against Lancashire and Surrey, and against the touring South Africans. His score of 168 against South Africa helped gain Oxford a first innings lead, though the match finished a draw. Amongst the crowd for the match was Pelham Warner, one of the selectors for the England cricket team, who enjoyed the innings so much that he invited Mitchell-Innes to play against South Africa in the first Test match at Trent Bridge. In a three-day match curtailed by rain, Mitchell-Innes batted once, scoring five runs before being trapped leg before wicket by Bruce Mitchell. He was retained for the second Test, but was suffering badly from hay fever, and wrote to Warner to advise him that, "I might be sneezing just as a catch came in the slips." Warner agreed, and called up Errol Holmes to replace him – Mitchell-Innes never got another chance to play for England. Hay fever also curtailed Mitchell-Innes' performance during the University match: despite being described as "the best batsman on either side" by Bolton, he was dismissed for scores of one and nought as Cambridge won by 195 runs.