Under the bright lights of the Spanish city of Palma, the second season of the UCI Track Champions League got underway on Saturday.

Races are divided into endurance and sprint categories.

The races will be divided into endurance and sprint categories, with the former being eliminations and scratch, and the latter sprint and keirin. Each round of the five-round series will have the same race program.

Rankings are based on points earned rather than time. Race winners receive 20 points, second place receives 17 points, third place receives 15 points, and 15th place receives 1 point.

In the 5km scratch race, Mark Stewart escaped with the main contender, Sebastián Mora, and finished one lap ahead of the rest of the pack.

The 27-year-old finished third in the elimination race and will leave Mallorca as the leader in the endurance category.

"When things go my way, it's great and I feel good. But I like to race hard," Stewart told Eurosport/GCN after the race.

"I put a lot of pressure on myself in the first few years of my career. Things had a meaning and it was part of who I was. I just want to ride my bike, I'm going to go have fun."

Compatriot Katie Archibald held off faster rivals in the women's scratch race, finishing ahead of Tania Calvo (Spain) and Jennifer Valente (USA).

However, her hopes as category leader were dashed when she finished first in the elimination race. Finishing second behind Anita Stenberg (Norway), Valente ended the night as the overall leader.

"This was huge," she said. I'm glad I still have some of my form [from the track world championships]." Asked how confident she is about keeping the leader's jersey, the Omnium World and Olympic champion replied: "I think consistency is everything. It is still too early to predict this series."

In the sprint category, world champion Harry Lavreisen (Netherlands) won the Keirin ahead of rivals Stephan Boettcher (Germany) and Matthew Richardson (Australia).

Richardson, however, upset Lavreisen in the sprint. Richardson said, "I tried something different that I hadn't tried earlier in the year, and it worked."

Meanwhile, French world champion Mathilde Gros won the women's sprint ahead of Hetty Van de Wouw, and Martha Bayona (Colombia) led the way and held off Canadian Kelsey Mitchell in the Keirin.

Stewart, Valente, Lavriesen, and Dutch sprinter Shanne Blaspeninckx will wear the UCI Track Champions League Cheleste leader jersey in the second round in Berlin on November 19.