Full-back Sito has been ruled out of Wednesday's trip to Leicester City. The Spaniard spent Saturday night in hospital after suffering a concussion in the early stages of Saturday's 0-0 draw with Burnley.
Physio Matt Byard says the ex-Racing Club de Ferrol man will be out for a week: "Sito suffered significant concussion which required treatment from the team doctor with support from the paramedics.
"He was taken to hospital and had a CT scan and was kept in overnight on Saturday for observation.
"He was discharged on the Sunday morning, but we have been advised by our doctor that because it was a bad head injury he has to rest this week and then look to resume light training after that."
Sito's absence, which is likely to extend to the Coventry game on Saturday, means Dan Harding will be recalled to the left side of defence at the Walkers Stadium. Matt Richards is back after his loan spell at Brighton, but will not be considered.
Town continue to look for their first win on their travels since March. Boss Jim Magilton again has to decide whether to employ the 4-4-2 formation which has been so successful at home or use the 4-5-1 which has been used away and is still to bring a victory.
After the particularly poor first half performance at Charlton, Magilton seems less likely to utilise the 4-5-1 formation this time around.
However the Town manager lines up his side, the back four will probably be unchanged other than Harding coming on for Sito, with David Wright on the right and Jason De Vos and Alex Bruce in the centre. Neil Alexander will continue in goal.
Richard Naylor is back in light training as he continues his recovery from a slipped disc in his neck, while midfielder Sylvain Legwinski is due to return to training this week after the ankle injury he suffered in training prior to the Scunthorpe game.
Magilton has midfield decisions to make with Danny Haynes never really impressing since coming into the right of midfield and Jon Walters less effective on the left.
The former Chester man looks likely to switch back to the right with Gavin Williams perhaps taking over on the problem left side. Owen Garvan and Tommy Miller will continue in the centre. Liam Trotter has a minor hamstring problem but is expected to train today and be OK to travel to the Midlands.
Alan Lee and Pablo Couñago look set to start up front with the Spaniard arguably Town's best away performer in recent weeks having been used as a sub. Haynes, Billy Clarke and Jordan Rhodes will all be hoping for some involvement from the bench.
Leicester have a doubt over midfielder James Wesolowski, who has a hamstring problem, while striker DJ Campbell is expected to be sidelined for three months with a pelvic injury. Elvis Hammond is also out with an ankle problem.
Town beat the Foxes 3-1 at Portman Road earlier in the month after the Midlanders had defender Patrick Kisnorbo harshly sent off for a foul on Pablo Couñago which led to the Blues' second goal.
Overall, the Blues have had the better of the Foxes in fixtures between the two clubs. Town have won 25 encounters (25 in the league), have drawn 15 (14) and have lost on 20 (18) occasions.
Probable squad: Alexander, Supple, Wright, Harding, Casement, De Vos, Bruce, Wilnis, Garvan, Miller, Williams, Trotter, Walters, Haynes, Roberts, Lee, Couñago, Clarke, Rhodes.