Dean Smith faces a selection dilemma for Saturday's FA Cup tie with Walsall as Brentford face season-defining league games against Middlesbrough and Burnley in the following six days.

If the Bees were to win those games then they would have to be considered as serious play-off contenders.

But, if they were to lose both, then the final months of the season are likely to be seen drifting towards a mid-table finish.

Some changes are inevitable but how many alterations to Smith's, seemingly, preferred starting XI is too many?

Humiliating: Brentford's much changed side were thrashed by Oxford

Bring too many of the reserves in and the Bees could open themselves up to another Oxford humiliation, which would be a marketer's nightmare when it comes to trying to sell cup tickets next season.

Given the quality Brentford have in some positions, a change will not make a major difference but, in others, it could noticeably weaken the side.

By going through the side who played against Birmingham we will look to identify the rotational changes to the side, without drastically weakening the team.

In goal

In goal: David Button

Goalkeeper – David Button

For me, the stopper was Brentford's best player over the course of 2015. Unlike outfield players, goalkeepers aren't normally rotated meaning the former Tottenham man should remain in the side.

Jack Bonham had a nightmare against Oxford, although to his credit publicly admitted his performance wasn't good enough.

Verdict: Button.

Defence

Up and at 'em! Ishmael Miller of Huddersfield and Jake Bidwell of Brentford try to win the ball from a corner

Right Back – Maxime Colin

This is where a decision to rotate is an 'easy' one. Colin has been excellent in his few performances for the Bees so far this season and has established himself as first-choice.

However, he must continue to perform as Nico Yennaris has been excellent in that position since coming into the side in October.

Josh Clarke is seen as a burgeoning right back but is now third-choice and, probably a long way behind the pair.

Verdict: Switching Colin for Yennaris will maintain the strength of the side.

Left Back – Jake Bidwell

Another easy decision. There is no recognised left-back in the squad apart from Bidwell unless you shift O'Connell or Barbet to full back.

Verdict: Stick with Bidwell.

Centre Backs – Harlee Dean and James Tarkowski

I'm a big believer in trying to maintain the spine of the team so, if changes are to be made, only one defender would be granted a rest. Due to transfer speculation, Tarkowski is the one to sit down with Jack O'Connell taking his place.

Verdict: O'Connell for Tarkowski. Barbet on the bench

Midfield

Sergi Canos celebrates his wonderful goal

Holding Midfielders – Toumani Diagouraga and Ryan Woods

With Josh McEachran coming back from injury it gives him a chance to put 90 minutes under his belt meaning one of the two is likely to be granted a rest or placed on the substitutes bench.

Alan McCormack will need time to get back up to match fitness after a month struggling with injuries.

Konstantin Kerschbaumer has dropped down the pecking order at Griffin Park but could be given a chance to prove himself.

Verdict: Bring McEachran in for one of Woods or Diagouraga, who becomes a substitute.

Attacking Midfielders – Sergi Canos, Alan Judge and John Swift

Transfer speculation means it would be prudent to give Alan Judge a rest and his performance at Birmingham fell short of the high standards he has set this season.

Jota has been struggling with a calf injury but if he is fit, then he is likely to be handed a start as well. It also presents a chance for Sam Saunders to come into the side and stake his claim for a place and a new contract with Akaki Gogia also an option.

Verdict: Rest Judge. Bring in Saunders. If Jota is fit to play an hour, use Canos as an impact substitute.

Up Front

Lasse Vibe scores for Brentford

Striker – Lasse Vibe

Vibe has performed well since coming into the side as a striker after Marco Djuricin's injury. With the Austrian returning to full fitness soon, the Dane could find himself on the bench or in the attacking midfield three.

However, there is a case to give Philipp Hofmann, who scored at Birmingham, a start. The German under-21 international has also shown promising signs and a 90 minute run-out would boost his fitness for the league tests to come.

Verdict: Hofmann starts, Vibe on the bench.

Overall

Philipp Hofmann celebrates scoring the winning goal

In total, that comes to five or six changes but Brentford would still have a side that is perfectly capable of beating Walsall.

The Saddlers will be especially keen to give Smith a hard time and show him what he is missing.

It would be very disappointing to see the whole team changed and a repeat of the débâcle against Oxford. The defeat did a lot of damage to former head coach Marinus Dijkhuizen's standing amongst the fanbase and Smith would be wise not to repeat it.

Team selections for the League Cup have suggested that it is a competition Brentford aren't really interested in, but the FA Cup is supposed to be the greatest competition in the world.

Memorable: DJ Campbell goes past Sunderland's Gary Breen to score the opening goal

The Bees have priced tickets for the tie really well but a repeat of what happened against Oxford will be unforgivable in the eyes of many.

Promotion glory seems beyond Brentford this season, given the strength of the top four or five teams, so a cup run would see an added bonus and a different form of excitement around the club.

Due to the FA hosting the semi finals at Wembley for financial reasons, it means the Bees are four wins from a day out at the national stadium.

Millwall, Wigan and Reading have reached the last four in each of the last three seasons while in the Championship in the past three seasons while League One side Sheffield United reached that stage in 2014.

Why can't Brentford do it? Realistically, they'd need to avoid the likes of Manchester City and co but it's within their capabilities to do so.