As night fell on the Doosan Arena, there was a strange mix of emotions among the Rangers fans as they filtered back into Plzen city centre.

There was, naturally, a degree of satisfaction among some of the punters that their team had progressed to the Champions League play-off round.

A couple of months ago, when Russell Martin took the job and the squad was undergoing the football equivalent of open-heart surgery, many doubted Rangers would even get this far.

Relief was probably the overriding emotion. Relief that Rangers hadn’t completely blown it, despite the Czechs winning 2-1 on the night whilst wasting several other gilt-edged chances.

There was also a sense of self-deprecation, with one Glaswegian voice heard saying to a Plzen stadium official as they left: ‘We’ll see you again in the Europa League in a couple of months.’

Cyriel Dessers hobbles off in Plzen and his absence is sure to be keenly felt

The Nigerian went down awkwardly and his manager later said the prognosis ‘was not good’

Martin could take few positives from defeat in the Czech Republic despite his side progressing

It was only a throwaway remark, but it summed up the lack of confidence and belief among a large number of fans about where this team is headed in Europe.

As things stand, the chances of Martin’s new-look side beating Club Brugge over two legs feel remote. You wouldn’t bet your last fiver on them beating Alloa at Ibrox on Saturday, let alone a team who reached the Champions League knockouts last season.

Granted, if they play like they did in the first leg against Plzen in Glasgow, Rangers should at least make a game of it.

However, play as they did in the Czech Republic on Tuesday night, Brugge could quite easily put four or five goals past them.

Martin spoke about this in his post-match media conference on Tuesday night. The gap between Rangers at their best compared to when they are at their worst is too big.

Part of the improvement and development of this team will be to show an ability to close that gap and to develop a more consistent level of performance.

Lyall Cameron was one of the few bright spots, his goal ultimately proving crucial

Much has been made of the style of play under the new manager, with Rangers hell-bent on playing out from the back regardless of what pressure their opponents put them under.

There has been a focus on Jack Butland, John Souttar and Nasser Djiga as the triumvirate at the back upon whom everything is built.

There has also been much debate about whether Nico Raskin should be playing ahead of Joe Rothwell as the single pivot at the base of midfield, or whether the Belgian international should be deployed further forward.

All of this places a focus on what Rangers are doing in possession, but nobody has really spoken much about the major problems when the team are out of possession.

In their six consecutive matches so far under Martin, Rangers have allowed their opponents to have 101 shots on goal. By anyone’s standards, that’s far too many.

They haven’t even played any opposition of any quality so far. It’s been Panathinaikos, Motherwell, Dundee and Viktoria Plzen.

Dundee defender Ryan Astley scores a looping header to flatten the Ibrox men last weekend

As soon as they come to play the likes of Club Brugge or Celtic, fans will be breaking out in a cold sweat with regards to what a good team might do to Rangers at the moment.

Even Hearts look like they could pose a huge problem on current form and their visit to Ibrox in September already looks huge.

Never mind Celtic for a moment. If Hearts were to go to Ibrox and win, putting even more daylight between themselves and Rangers, they could become Martin’s biggest problem. He would be in major trouble.

The Ibrox boss also spoke on Tuesday night about how certain aspects of the performance ‘annoyed’ him. Namely, after playing out from the back and breaking through Plzen’s press, the ball was not sticking up front.

Cyriel Dessers had an awful game prior to limping off with a knee injury. His hold-up play was non-existent and he was easily outmuscled by the Plzen centre-backs.

So effective in the first leg in Glasgow, wingers Djeidi Gassama and Oliver Antman also struggled to make an impact.

Gassama enjoyed a blistering start to life at Rangers but has been quiet on his last two outings

But it was the injury to Dessers which now raises the prospect of Rangers needing to go back into the transfer market.

Truth be told, they have been looking at adding a new striker all summer, even prior to Dessers hobbling off and leaving Plzen in a knee brace.

Neither he nor Danilo will be the solution long-term. Neither of them have the technical skills to play in Martin’s system, although Danilo did make a difference when he came on in Plzen.

They are both inconsistent and unreliable. None of this is new to Rangers. They have known this for a long time, and both Martin and sporting director Kevin Thelwell have been working to identify possible striker targets.

After a nervy and unconvincing display in Plzen, the upside for Rangers is that they will now bank a guaranteed £3.7million thanks to reaching the Champions League play-off round.

The Rangers squad applaud their travelling fans in Plzen but they need to move up a gear

That is undoubtedly a welcome boost. But, from Martin’s point of view, he needs as much of it reinvested into the squad as possible.

Not in January or next summer, but right now, before the summer window slams shut at the end of August.

How much money is actually left from the initial investment of £20m pledged by the club’s new American owners?

Not all of that was to be pumped straight into the playing squad, but Rangers have still spent close to £15m on new players so far this summer.

There are players yet to be integrated into the team in forward areas. Hamza Igamane, Thelo Aasgaard and Mikey Moore are all expected to feature against Alloa in the Premier Sports Cup on Saturday.

How Martin chooses to utilise Aasgaard and Moore will be interesting. They are both attacking midfielders who can also play out wide if needed.

Mikey Moore is one attacking option for Rangers but it is unlikely he will fill the void up front

Igamane can play centrally and is a better option than Dessers or Danilo, but the smart money still feels like Rangers will probably cash in on the young Moroccan before the end of the window.

If an offer of around £15m was to be received, they would bank a tidy profit, move him on, and reinvest the money.

Yet, as attention now turns back to domestic matters this weekend, one thing is clear. If Rangers do manage to furnish Martin with any more new players before the end of the window, it must be a new striker.

The need for a new No 9 could scarcely be more obvious than if the club painted it on a giant billboard and advertised it on Edmiston Road.