The City winger missed the dramatic midweek win over Southampton after suffering from a fever.
But he trained on Thursday with the rest of the first-team squad and is in contention to return to Pep Guardiola’s starting line-up as City go in search of 20th-consecutive win against the Hammers.
“He was sick,” Guardiola told journalists. “He had fever the day of the game against Southampton.
“And now yesterday he was in the training session.”
Sane is one of three City players on the cusp of a ban after collecting four yellow cards.
Guardiola says he is yet to decide his team to face West Ham and will use Saturday’s training session to make his final preparation - but admitted with such a packed December schedule, he needs to keep the side fresh.
“We will see tomorrow,” he said. “Tomorrow we train and we will see what we can do.
“Vincent was two months injured, Fernandinho has played a lot of minutes - but the most important thing is West Ham.
“I am worried about the bookings, United is an important game, but West Ham is as well.
“Last game, we didn't play David [Silva] from the beginning, I rotated.
"Nine games in one month...every player has to play.”