The duo were sidelined for last Saturday's 3-2 defeat at Notts County through injury. Veteran striker McGleish was missing with a neck problem while defender Forbes was suffering with a thigh strain, but both have trained this week and are set to return.
Aaron Brown, who replaced Forbes in the back four at Meadow Lane, has been struggling with a knock which has restricted his training this week and he will have a late check.
Defender Charlie Daniels came through his comeback from a hamstring injury unscathed and will start at left-back again.
Striker Jonathan Tehoue is still missing with ankle trouble. Meanwhile, penalty hero Richard Lee has given Brentford manager Andy Scott a selection dilemma.
Lee only started Tuesday night's Carling Cup tie against Everton because Reading loanee Ben Hamer, the Bees' regular first-choice, was ineligible. And the former Watford keeper staked his claim with a string of fine saves before keeping out Jermaine Beckford's spot-kick as Brentford won a dramatic shoot-out.
On-loan Huddersfield striker Robbie Simpson has missed the last three matches with a hamstring injury but is close to returning and will be checked over.
Midfielder David Hunt is still out with damaged ankle ligaments and summer signing Kirk Hudson is building up his fitness following a groin problem.
Source: DSG
Source: DSG