Callum O'Dowda successfully came through his comeback match in the 2-0 defeat against Millwall on Saturday following a lengthy absence while he recovered from an ankle injury.
And Hordur Magnusson returned to training on Monday as he stepped up his recovery from a knee injury, with City looking to put themselves back in the Championship play-off picture.
The Millwall loss left them four points outside the top six with five games left.
Birmingham's worries are of the relegation variety, but they have hit a patch of good form under new manager Garry Monk.
Che Adams will miss the trip to Bristol because of suspension, with Monk hoping that Sean Gallagher can overcome a calf muscle problem to be in the selection mix, or it could mean another out-of-position start for Jeremie Boga.
Midfielder Craig Gardner, meanwhile, could feature after returning to training.
Birmingham currently occupy 20th place in the Championship, one point above Bolton and two behind Reading.
Manchester United target Toby Alderweireld says he is unsure what the future holds, while Harry Maguire is also said to be a target.
Arsenal are reported to be showing an interest in Real Madrid midfielder Mateo Kovacic but will be put off by the asking price.
Celtic skipper Scott Brown insists Champions League football remains key even after more than a decade at the club.
Brighton have completed the signing of midfielder Yves Bissouma on a five-year deal from French side Lille.
Rafael Benitez has admitted he will have to 'wheel and deal' this summer if he is to get the men he wants to rebuild his team.