Thompson was unavailable for the game against Swindon, but after the fixture was postponed due to a waterlogged pitch, the one-match ban will now come into effect, ruling the 21-year-old out of the game at Broadfield Stadium.
Magnus Okuonghae is the likely candidate to earn a recall in the centre of defence, after he played 77 minutes as a substitute in the Boxing Day defeat at Brentford.
The U's have Freddie Sears available after he missed the Bees clash with a dead leg.
The postponement of the game against Paolo Di Canio's side has worked to the benefit of Jabo Ibehre who should have recovered in time from a pulled stomach muscle to fight for inclusion.
Anthony Wordsworth was dropped from the 16-man squad completely on Boxing Day, and he could be left out of the travelling party again against the Reds.