The Dimension Data leader lost out to Julien Vermote (Etixx-QuickStep) on a brutally tough day of racing, conceding a handful seconds to the Belgian on the steep rise to the finish in Kendal. However, with a time trial coming late in the race, as well as summit finish to Haytor, the Tour de France stage winner gained almost a minute on a group containing Tony Gallopin (Lotto Soudal) and Tom Dumoulin (Giant Alpecin).
"Obviously I was going for the stage from the start but with who I was with, the best option was to then gain time on the others. I was racing for time in the end rather than the stage," Cummings told Cyclingnews at the finish.
The stage from Carlisle began with a 15-rider break escaping from the bunch. Vermote, who last tasted victory back in 2014 at this very race, was part of the move but Cummings and several rivals countered and caught the remnants of the early move on the appropriately-titled ascent of The Struggle.
Cummings made a bid for glory over the top of the summit but was brought back by Rohan Dennis (BMC). However, when Daniel Martin attacked Cummings was on him in a flash. Vermote matched the acceleration with Martin dropping back to leave the pair at the head of the race.
The two riders held talks before working together in order to distance the chase that was led by Team Sky, who had two men working to peg them back. Cummings carried out the majority of the work with Vermote pitching in at several points.
The final 500 metres were all uphill and Cummings, the favourite on paper, was unable to hold Vermote when the Etixx rider opened up a small but decisive gap. The British rider was still full of praise for his breakaway companion, who later confirmed that he would not be targeting the overall despite now leading the race by six seconds over Cummings.
"He was giving me what he could and he's a really good lad and a super racer. He's such a good worker and I'm happy for him because he deserved it after being in the break all day," Cummings said.
With six-man teams, relentlessly demanding stage profiles and riders at such varying degrees of form, the Tour of Britain is a hard enough race to predict, let alone control.
Although Cummings now has a collection of his main rivals out of the running on GC, that factor in itself throws up a new set of problems. Riders like Gallopin, Dumoulin and those even further back will need to take risks and ride aggressively if they are to move back into contention. The 15km time trial later in the race offers one key opportunity but Cummings is wary that each stage holds its own pitfalls as well as its own chances.
"Going into the time trial it looks quite good for me but every day is difficult here. I'm happy with my shape. I need to make some good adjustments coming into September and need to be a bit lighter and then I'll be better on the climbs but this is really good. It was a really good test. We just go day by day because it’s so difficult to control. I've put myself in a good position but it could all turn around again tomorrow."