Chris Froome moved into the yellow jersey with a stunning downhill attack to win stage eight of the Tour de France into Bagneres-de-Luchon.
The two-time winner and defending champion led a select group of riders over the top of the Col de Peyresourde and immediately accelerated away, ultimately taking victory by 13 seconds from Ireland’s Dan Martin of Etixx-QuickStep, who led the chasing pack home.
With BMC’s Greg Van Avermaet dropped early on a challenging day in the Pyrenees, Team Sky’s Froome assumes the overall lead of the race.
It was the fifth victory for a British rider in the first eight stages of this Tour.
Cummings’ compatriot Mark Cavendish had already won three of the first six stages for the African outfit.
South African Daryl Impey took second on the stage ahead of David Navarro of Spain.
Belgian Greg Van Avermaet finished fifth and extended his overall lead in the yellow jersey competition ahead of Frenchman Julian Alaphilippe and Alejandro Valverde of Spain.
But there was controversy when the peloton of leading contenders arrived to find the inflatable arch indicating the final kilometre had collapsed, taking down another Briton, Adam Yates, as he passed beneath it.
The 23-year-old Orica rider eventually finished the stage with blood on his chin.
The expected fireworks on the first major climb of this year’s Tour never materialised, though, as the favourites, including reigning champion Chris Froome and Colombian Nairo Quintana, made no attempts to attack each other.
But French hope Thibaut Pinot suffered badly on the climb and lost around 2min 30sec.
For Cummings, an Olympic silver-medallist and world champion from the track in the team pursuit, it was a second stage victory in successive years.
Mark Cavendish moved into second place all-time for Tour de France stage wins as he collected his 29th victory on stage six in Montauban on Thursday.
Cavendish’s third win of the 2016 Tour came ahead of Germany’s Marcel Kittel, and a fine third place for British Tour debutant Dan McLay – his fourth top-10 finish of his opening Tour.
Cavendish’s victory on stage three had moved him level with five-time Tour winner Bernard Hinault on 28 Tour stage wins, but he is now alone in second place and five behind Eddy Merckx’s record of 34.
Cavendish sat on the wheel of Etixx-QuickStep’s Kittel as they came into Montauban, and launched himself forward in the final 200 metres.
Finishing fastest of all was Fortuneo-Vital Concept’s McLay but the 24-year-old ran out of road as Team Dimension Data’s Cavendish punched the air for the third time this week.
@MarkCavendish started with a strong kick & I couldn't get him back till the line. Congrats! I will have to wait till the next chance! 😈— Marcel Kittel (@marcelkittel) July 7, 2016
The 31-year-old has enjoyed some fantastic Tours in the past, winning six stages in 2009 and five each in 2010 and 2011, but has never before collected three wins in the first six days.
“Oh my god, that was terrifying,” Cavendish said. “That was like the old days, wheel surfing. I was a little too far back going into that so it was just carnage in the final. I wanted Kittel’s wheel and I was fighting for it.
“I knew it would be the right thing to go early because it was slightly downhill, I put the bigger gear on again but I maxed out and should have put a bigger gear on. I held on and held Kittel off, did to him what he’s done to me over the last three years.”