Luton find themselves at the foot of the Championship table again after Wigan Athletic and Barnsley both picked up vital wins at the weekend and Graeme Jones's side enter Tuesday's fixture six points from safety.
The club have not had an issue with creating chances this season but they have been very poor at the back and they currently have the leakiest defence in the division.
Their defenders have struggled aerially, which could be a problem at set pieces against a Brentford side containing Ethan Pinnock, and against quick, skilful players, of which the West London club have several.
However, the added pressure of trying to avoid relegation has seen Luton's form upturn since the start of the year, with the club winning three of their last six in the league.
Conversely, Brentford are currently fourth in the table and they currently have the best defence in the league, conceding just 29 goals in 34 games.
Worryingly for Luton, Brentford are averaging more than 14 shots a game at the moment and they won the reverse fixture 7-0 back in November.
Watkins netted his 21st of the campaign at the weekend and the 24-year-old is currently getting 64% of his shots on target.
Mbeumo was a doubt for the game with Blackburn but he was able to last the full game and his presence will be vital for Frank's side as they look to end a streak of three consecutive draws and put pressure on the top two.
Luton Town competition form: WLLWWL
Brentford competition form: LWWDDD
Isaiah Brown missed the Charlton game through illness but Jones will be hoping that he's fit enough to play a part on Tuesday.
Emiliano Marcondes has started the last two games for Brentford but the Argentine may drop out for this midweek game, with Frank wanting to keep his squad fit for the run-in.
The most significant absentee for the West London club is Swedish defender Pontus Jansson, who remains out injured.
Luton Town possible starting lineup:
Sluga; Bree, Pearson, Carter-Vickers, Potts; Shinnie, Tunnicliffe, Moncur, Berry; Cornick, Collins
Brentford possible starting lineup:
Raya; Dalsgaard, Jeanvier, Pinnock, Henry; Baptiste, Norsgaard, Dasilva; Mbeumo, Watkins, Benrahma
We say: Luton Town 1-3 Brentford
Luton's need for a result will likely see them get on the scoresheet but Brentford should have enough pace and quality in the attacking areas as they look to maintain their promotion push.