The winning factor Paulo Bernardo needs to net permanent Celtic deal

He's even started to play the part. Impressive goals against Dundee and Rangers as well as two assists in the match against St Mirren helped Celtic plunder all 12 points from four matches during the Festive period as Brendan Rodgers's side entered the winter break eight points ahead of their city rivals at the top of the Scottish Premiership.

Granted four games do not make a season. Still, former Champions League winner and Parkhead legend Paul Lambert has watched closely as the Portuguese midfielder has propelled himself from the periphery of the first team onto the full glare of the spotlight on centre stage.

The on-loan Benfica academy graduate is available for Celtic to buy at the end of the campaign, however, Lambert reckons the Scottish champions will need a bigger sample size to fully judge to justify any purchase come the summer.

However, based on the recent evidence the ex-Hoops captain admits that if the 21-year-old can continue this level of consistency he will put up the strongest case yet to be involved in the contract discussions.

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He said: "Sometimes it can take players a full season to settle in at a club like Celtic. Others can hit the ground running and it clicks straight away. Then you get those that it may take six months or so and then they just flourish.

"Paulo Bernardo has come from Portugal and has had to learn a lot in the short time he has been here but he may fit into the latter category. In the last four games, he has raised his levels and he has performed well.

"It's a start for him in terms of his Celtic career. He has now shown the Celtic fans and the manager that he can do it. The secret and trick now is to do it week in, week out. You don't get time at Celtic to do it once in every five matches. He has to do it every single week. Bernardo seems to be quite level-headed as well as humble with it, which are two great traits.

"I have watched Bernardo play up until this point and he has seemed to be on the periphery of things but not anymore. He seemed to be content with being one of the starting eleven. There was nothing great and there was nothing bad in his performances. At Celtic, you have to produce something whether you are a defensive midfielder or an attacking midfielder, you have to make something happen.

"Bernardo was constantly in and out of the team and he hadn't established himself as a mainstay of the side. Now all of a sudden it has all changed for him. The consistency levels are not just measured over four games it is year after year and season after season. You only need to ask Callum McGregor about that. That's the key and secret to it all. You can never drop that high standard. That is how you kick on as a player within a team.

"The good thing about Bernardo is that he showed his worth against Rangers with his goal and overall performance. His assists for both Matt O'Riley and Greg Taylor against St Mirren were excellent. That is conclusive proof that Bernardo is a more confident player now in a Celtic jersey and he is starting to try different things.

"I saw him play against Lazio and I wasn't overly impressed as I thought the game passed him by. He did a lot of running but it was not coming from his brain it was just coming from his legs. As he gets older, he will learn the midfield role and Brendan will educate him as well. In the midfield, good players play with their brains and not their legs most of the time.

"Bernardo gets into the box which is a good thing and he has shown that he can net goals for Celtic. He is only 21 and there is a lot of learning for him to do and education to pick up. The carrot being dangled in front of Bernardo now is that the next five months will determine whether he wins a permanent contract at Celtic or not. If he does well and both parties agree then he will sign the deal. If he doesn't then Brendan will need to decide on what he wants to do with him.

"In the last few games, Bernardo has started to get going a bit but he has to sustain those levels from now until May."

Bernardo ingratiated himself to the Celtic faithful with a stunning opening goal in the 2-1 Glasgow derby success at Parkhead on December 30.

It was his first experience of the powderkeg fixture but he produced a moment of genuine quality as his half-volley flew past Jack Butland like a bullet after 25 minutes.

Lambert is no stranger to that feeling himself as his first ever Celtic career goal came against Rangers in the New Year derby of 1998 when he crashed an unstoppable 25-yarder past Andy Goram.

The former Borussia Dortmund and Scotland star admitted that Bernardo now has to show that he can keep pulling top-drawer displays out of his locker. If Bernardo continues on an upward trajectory then Lambert knows he will also learn valuable football life lessons that he can retain for the rest of his career.

"It was a great strike as he got right over the ball and caught it with his laces. Bernardo showed superb technique and that goal set Celtic up for the win," he continued.

"That's two goals and two assists from Bernardo in his last four games and these are the levels that not just Bernardo but every Celtic player has to aspire to. In the last few games, Bernardo has hit the level but as a Celtic player, that level has to be constant and consistent. He has to be bang on it all the time and I mean every single week when you play for Celtic. If you don't produce every game then everybody knows what happens.

"Whether you are a young player at Celtic coming through the ranks, or just a young player or an experienced player, the one thing that this club teaches you is that you have to win. You have to win at every level. If you don't have that feeling of winning, you crave it. It is like a drug. You always need it. It gives you a great grounding.

"If you do happen to move on from Celtic to pastures new then players quickly find out that there are not many clubs like it. The demands that are placed on Celtic players are incredible. That feeling of having to win games is ever-present at Celtic. The fan base demands that you win football matches. The lessons you learn at Celtic stand you in good stead whenever you do leave the club.

"Even Bernardo will know by now that the mentality at Celtic is that you cannot even draw a match. That is a great thing. You have to be able to handle that as well as the crowd even when things are bad or else it will eat you up. It's exactly that kind of attitude which should drive Bernardo on as he pursues a permanent contract with the club."

If Bernardo can turn it on during the remaining months of the loan spell then he only needs to look at what happened with fellow countryman Jota who went on to become a Celtic hero and club icon after a similar loan with an option to buy clause was activated.

The winger enjoyed a fabulous relationship with the Celtic supporters before he upped sticks and joined Saudi Arabian outfit Al-Ittihad for £25 million in the summer.

Lambert said: "Jota was a fabulous player for Celtic but his career has stalled since he left to sign for Al-Ittihad. Bernardo can follow in Jota's footsteps to an extent in terms of the loan option to buy with Celtic.

"If Bernardo keeps on doing what he is doing and he has good people around about him then he can decide for himself if he wants to stay here. If he chooses to sign for Celtic permanently then the rest is up to him as he is still young and there is plenty of time to grow, progress and advance your career."

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Lambert is convinced that Bernardo can only learn from the likes of captain fantastic McGregor as well as Matt O'Riley who is having the campaign of his life. With Reo Hatate also back from injury and looking to cement his place in the engine room once again then the 54-year-old reckons the conditions are ripe for Bernardo to prosper at Parkhead.

"The Celtic midfield is the strongest part of their team. Callum McGregor is an inspirational figure and the skipper is an automatic starter for me every week," he added.

"It might seem simple Callum possesses the great art of passing the ball to somebody in the same shirt. Some players find that difficult. He is a player who plays one and two-touch football and keeps it simple.

"Matt O'Riley is going through a purple patch right now and is performing to a high standard. Reo Hatate is on the way back from injury and that will be great for Bernardo's levels moving forward.

"He has had a small taste of regular games with Celtic and he will not want to drop out of the team now. That will ensure that the levels are kept extremely high. Bernardo will know that if he doesn't perform then there will be another guy to take his place."

Lambert's own personal jury may well be out as to whether Bernardo is in the Jota mould and if he will be another superstar from Portugal.

Like many Celtic supporters, Lambert is keen to reconvene the discussion in five months. If the last four games are anything to go by then Bernardo has given himself a fighting chance of winning a new contract at Celtic. He only has to sustain his current form to make that happen.

As Lambert said: "Winning at a club like Celtic is a drug you always need and crave."

That being the case Bernardo will simply need to develop an addiction to both over the next five months - Celtic and winning - that is.