The eight potential challengers who began the Candidates tournament in Toronto on Thursday have an ­unfamiliar feeling. Whoever wins will be a firm favourite to ­capture the crown from the struggling holder, Ding Liren, instead of being the ­outsider of two against Magnus Carlsen, who abdicated his title while still at his playing peak. For the first time, the Women’s Candidates is being held simultaneously.

The games will be shown live on Fide YouTube starting at 7.30pm BST daily, with commentary from the ­former world champion, Vishy Anand, and the No 1 US woman, Irina Krush. The best viewing site is likely to be on Chess24’s channel where England’s David Howell and the all-time No 1 woman, Judit Polgar, are the lead commentators. Another excellent choice is the ad-free Lichess commentary by England’s Matthew Sadler and others. All first-round games bar one were drawn, with China’s Tan Zhongyi beating her compatriot Lei Tingjie in the women’s event.

Carlsen, now a former world champion but still the No 1, scored his sixth tournament victory in a row when he won first prize in the Grenke Classic at Karlsruhe, Germany, last weekend. His previous five were the Champions Tour final, the World Rapid and World Blitz, the Chessable Masters, and the Freestyle Challenge.

It was not smooth sailing, as the 33-year-old Norwegian lost in the first round to Richard Rapport and should have been beaten again when they met in a final play-off. The computer showed +99 for the Romanian, who had the No 1’s white king trapped on the eighth rank by the black rooks and simply needed to push his free g pawn, but he missed it due to extreme time shortage.

Ding arrived in Karlsruhe needing a good result to offset his failures this year at Wijk aan Zee and the Freestyle Challenge, but it did not happen. Ding finished fifth of six, including a run of 27 games without a win. He looked listless, but there were a couple of positives. First, he drew both his games with Carlsen in their first meeting at classical chess since the world title changed hands; second, he confirmed that he will be competing both in Norway next month, where Carlsen again awaits, and for China in the Budapest Olympiad in September, as he tries to regain form for his title defence.

It is an open Candidates, realistic ­contenders. Fabiano Caruana and Ian ­Nepomniachtchi have done it before, Hikaru Nakamura narrowly missed out in 2022, Alireza Firouzja at his best is the young pretender, while Praggnanandhaa R, ­probably the best of the three male Indian ­players in the field, will have the wise eight-time Russian champion Peter Svidler as his second.

Caruana, the US champion, is the general favourite, due to his ­consistent form over many years, his tied 2018 championship match (before tie-breaks) with Carlsen, and his ­classical, rational and controlled style of play. Yet there is a view that the 31-year-old has become more ­vulnerable to ­choking at critical moments, as he failed in the last two Candidates and in the recent American Cup.

Nakamura would be a popular ­winner, The streamer with more than a million followers is liked and admired for his fast-talking ­narratives and his remarkable blitz skills. He could have qualified for a title match with Nepomniachtchi in 2022, but spoiled his chance by passive play against Ding in the final round. At 36, he would be old for a first-time challenger, although Viktor Korchnoi and Boris Gelfand did it in their 40s.

Nepomniachtchi’s two previous Candidates were preceded by high-profile publicity for his aides and a Moscow super-computer. This time, it has been much more low-key, as have the Russian’s recent tournament appearances such as his 50% score at Wijk aan Zee.

He has the strongest motivation of all the candidates, as he led three times against Ding in 2023 and missed several opportunities to win the match. His quoted odds to win the Candidates this time, based on current Fide ratings, are only around 10%.

Alireza Firouzja is only 20, but already has a long career. He was one of the favourites in 2022, but finished only sixth and has since spent time on an alternative career in fashion design before his last-minute qualification via a controversial route. He is an exceptional talent, but now there is a question mark over his consistency.

Teenagers have a poor record in the Candidates, so although Praggnanandhaa, 18, and Gukesh D, 17, will have encouragement from tens of thousands of Indian fans, this Candidates may be a learning experience. The third male Indian in the tournament, Vidit Gujrathi, qualified via the Fide Grand Swiss but he is rated only world No 25, while Azerbaijan’s Nijat Abasov is a 100-1 outsider.

My hesitant selection is Nepomniachtchi for a third victory, although I would not be shocked if Caruana, Nakamura or Firouzja won. Who is the choice of Guardian readers?

The women’s Candidates looks easier to forecast. Russia’s ­Aleksandra Goryachkina and China’s Lei Tingjie are the two highest-rated ­players, both have won the ­Candidates previously, and both went close in their world title matches against the holder, Ju Wenjun. My narrow ­preference is for the Russian.

3914 1….Qh8+! 0-1 If 2 Kd5/e4 Qh1+ skewers White’s king and queen. If 2 Kf4 Bd6+! and now if 3 Qxd6 Qh2+ wins the queen, 3 Ke4 Qh1+ skewers, while 3 Kg4 Qh5 mates. If 2 Ke6 Qh3+ when if 3 Kf6/e5 Qf5 mate or 3 Kd5 Qh1+ skewers. If 2 Qf6 Bg7 wins the queen.