A TRICKY thing about raising the bar is that it becomes increasingly 
difficult to then take it up a further notch or two.

Or in the case of football, in particular Brendan Rodgers’ Celtic, it costs a lot of money to improve something which is already in pretty decent shape.

A few million quid is not going to buy a player better than any he already has.

Read more: Brendan Rodgers reveals John McGinn is set to sign for Celtic with Scott Allan off to Hibs

This is why the manager is not doing his summer shopping in the bargain bins.

Odsonne Edouard cost a club record fee of £9million, a sum of money Celtic would never have spent on one player even a year ago, and with John McGinn looking set to come in as well – he is going to cost a few bob, if not the £5m Neil Lennon wanted – the next new man’s price tag will have a fair few zeroes.

After two seasons, Rodgers finds himself in a position wherein he doesn’t need a squad player, because, with all due respect, there are more than enough impact players already at Parkhead.

Celtic are looking for one more creative type, they are never cheap, and when the next summer signing is made, it will be for someone who can walk right into the team.

Rodgers said: “We need to strengthen. That’s something I’ve said all along. It’s about bringing players of the right quality in. It’s not a numbers game for us. We have a core squad that is very strong. We want to add to that.

“I don’t need to add guys who will be on the bench. I want guys who can come in and affect the team.

“We lost a couple of important players in Stuart Armstrong and Patrick Roberts, who was on loan. We need to replace that quality – and, if possible, add to it. That’s our job over the next couple of weeks.

Read more: Graeme McGarry: Eight games to Champions League groups, but Celtic look fit for a fight​

“To improve us, the reality is that there has to be investment. We can’t deny that. If you want to improve and develop, that is important for the squad.

“But the players here have developed very well, players who have been fantastic for me for two years.

“To bring someone in who is ahead of them is going to take money. I’m working with the squad we have and we look to develop it, make the boys here any better.”

Celtic face Shamrock Rovers in Dublin today before they fly to Armenia tomorrow where on Tuesday they will face Alashkert in what is sure to be the searing heat.

The double Treble winners will get through this round but this first game of the first qualifier will prove a test.

“Of course, it’s always difficult if you are playing in extreme heat like that,” said Rodgers.

“We have to monitor the blocks of pressure we put on in the game. It’s hard to press for 90 minutes, that’s for sure. So it’s about how you prepare the players tactically, as much as physically. Maybe it can’t be a full-pitch press, just a medium-pitch press and even lower at times. You are preparing the players for that.

“We’ve done as much preparation as we possibly could. We’ve got a lot of decent coverage and John McGlynn has been out to see them and analyse them. We will be prepared.

“At this stage of pre-season, the players will never be 100 per cent.

“But I’ve been really impressed by how the guys have come back. They’ve come back fit, which is how the top modern-day player should be.

Read more: Brendan Rodgers reveals John McGinn is set to sign for Celtic with Scott Allan off to Hibs

“They have a high level of fitness, then we look to push that and extend that over the first few weeks.”

Dublin is not Armenia but it will be another run-out for a group of players who are now desperate to get started for real. Enough of these friendlies already.

“It’s another step towards our match fitness,” said Rodgers. “It’s clear that you have to work your players very, very quickly ahead of the qualifiers.

“We’ve had a very good week at Lennoxtown, followed that up with another good week in Austria – and now we continue 
that preparation.

“We had a great time here last year so, at this stage of the season, it’s good for us.

“We’ve had a lot of important work to do because, once the competitive games kick in next week, it’s hopefully right the way through until virtually the end of August.

Read more: Graeme McGarry: Eight games to Champions League groups, but Celtic look fit for a fight​

“But the players, at this stage of pre-season, are looking very strong. We still have a lot of work to put into them. There will be a team that will play probably 60-70 minutes of the game, then we’ll make changes. You can’t protect them too much because you still need to build fitness.

“Next week, you will be looking to push them for 90 minutes. But bearing in mind it could be 38 degrees. These are competitive games very early – but we also have to build the players for the whole 
of the season.”