Grant got his marching orders after just 26 minutes, but less than two minutes later Kevin Betsy struck the only goal of the game.
The win was the in-form home side's fifth in a row and left Mark Wright's team looking for the first triumph in six games.
The game started quietly, with Wycombe's midfield enforcers trying to impose themselves on the away side, but their clever passing could not breach a packed Chester defence.
Events livened up after a vicious clash of heads between Grant and David Artell which saw them both booked.
The confrontation turned the match into an ill-tempered affair and it was no surprise when Wycombe's on-loan Chelsea midfielder Grant picked up a second yellow card for kicking the ball away.
However, this seemed to revitalise the home side, who took the lead moments later when Scott Golbourne's precise cross was met by the head of the unmarked Betsy who thundered the ball in to the top corner.
Wycombe's veteran striker Tommy Mooney was forced off with blood pouring from his face shortly before the break after a challenge with Paul Linwood.
There was time for Chester to squander a great chance before the referee blew for half-time, Jon Walters slashing a volley high and wide.
City came out more determined in the second period while Wanderers seemed content to hang on to their lead and changed to a more defensive formation.
The visitors' Drewe Broughton tested goalkeeper Ricardo Batista on 52 minutes with a decent half-volley from 20 yards.
Chester continued to huff and puff, having the lion's share of possession, but Will Antwi and Mike Williamson stood firm at the heart of the Chairboys defence.
And the longer the second half continued, the more comfortable Wycombe looked, with Betsy and Sergio Torres getting into some dangerous positions on the flanks.
The best chance of the closing stages fell to Wycombe, Betsy dispossessing Kevin Sandwith on the halfway line and embarking on a mazy run before shooting straight at keeper John Danby.