ATP Tour Finals Preview and Tip: Back Ruud to end Rublev's season at 5/4

• Alcaraz tough task versus Zverev

• Ruud has clear opportunity

• Back Ruud to continue in Turin at 5/42.25

It looks set to be a dramatic finale in the John Newcombe group at the ATP Finals in Turin.

Carlos Alcaraz was the favourite to emerge from this group as the winner, but the Spaniard has been struggling with illness this week and his passage to the semi-final looks difficult as he must defeat the in-form Alexander Zverev.

The German is playing well at the moment, comfortably winning his last seven matches and even though his qualification position is strong and he can possibly even afford a slip up against Alcaraz, I would be surprised if this will be in any way easy going for the reigning Wimbledon and French Open champion.

Alcaraz started like a house on fire against Andrey Rublev to suggest his form is there. However, he is fending off an illness and played the full match with a nose strip, which I hadn't seen an athlete wear since the peak years of former Liverpool striker Robbie Fowler in the nineties.

The poor health of Alcaraz was obvious to my eyes as he could not sustain the level of his initial fine start, struggling to pull away from Rublev in set two and even needing to fend off a couple of Rublev set points. He surely can't afford any inconsistency against the rock-solid Zverev.

Despite these concerns, odds compilers are placing their faith in Carlitos to get the job done. To me that feels too much of a leap of faith given Alcaraz's health issues and the form of Zverev. Alcaraz needs a convincing win against an in-form opponent and while you'd be a fool to write off Alcaraz, it is a stretch even for a talent as special as the Spaniard.

Casper beneficiary of Alcaraz's Ruud health

At the start of the week it was Casper Ruud who benefitted from Alcaraz's weakened condition. The Norwegian was the tournament outsider before a ball was struck.

Ruud qualified because of his stellar work in the clay season between April and May. His results in the other eight months of the season were disappointing.

Even though that's the case, Ruud should not be discounted when he is feeling confident. You don't reach the US Open final in your career if you can't play on a hard court.

He should fancy his chances of defeating Andrey Rublev, who has looked like he'd rather be any place but a tennis court these last few months.

The Russian has not pulled up any trees in his matches in Turin so far, falling short as expected against both Zverev and Alcaraz. With only the most unlikely sequence of events gaining him access to the semi-final, he is playing only for pride.

Ruud on the other hand has a win under his belt, which he earned against Alcaraz in the opening match. Although after the contest Alcaraz was revealed to be under the weather, but it wasn't obvious during the match.

He then put in a commendable showing against Zverev, matching his opponent step for step with the only difference between them being in the tie-break and the solitary break point that Zverev created and converted deep in set two. Ruud's form is competitive.

The bad news is his fate does lie slightly out of his hands as a straight sets Alcaraz win over Zverev creates the scenario where Ruud could be eliminated if he happens to have lost a lower percentage of games than Alcaraz in the case of a two sets win for each player in their respective matches, or potential elimination should Ruud only secure the victory in three sets.

There is plenty to play for, but given the challenges ahead of both players I see value on Ruud at least getting his part of the job done.

Ruud should believe

Ruud and his entourage have talked all week about his positive form and his current level of confidence.

Zverev also added positive words after their match saying, "I have never seen Casper play so well on hard courts like this."

As for Rublev, he has offered some excuses for his defeats to Alcaraz and Zverev describing the quality play of both players. Whilst he is not exactly wrong in these statements, it does feel like projection when taking into account his own overly positive appraisal of his recent form.

I have felt for some time that Rublev could do with some time away from the courts, and it would be a surprise if he suddenly clicked into gear for his final match of the season.

They have not played for some time but Ruud has actually won two of their last three encounters, both of which have taken place at the Tour Finals.

In theory Rublev can exploit the Ruud backhand, but considering how well it has held up in his matches against Zverev and Alcaraz, there is no good reason why Rublev should be able to do better than them. It is difficult to justify Rublev's favouritism.

Form and confidence are both n Ruud's favour ahead of this match, and the Norwegian is the only player with a realistic chance of remaining in the tournament. At 5/42.25 there is plenty of reason to side with Ruud.

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