Dennis takes yellow jersey on opening day of Tour de France
Chris Froome was content after an opening stage of the Tour de France where an Australian overhauled an Englishman's record at the start of an Ashes summer.
Rohan Dennis claimed the first yellow jersey of the Tour with victory on the 13.8-kilometre stage one time-trial in Utrecht and broke Chris Boardman's 21-year-old top speed record in the process.
The 25-year-old's average speed of 55.45kph on the technical, twisty course was the fastest recorded in Tour time-trials as Dennis surprised multiple world time-trial champions Tony Martin (Etixx-QuickStep) and Fabian Cancellara (Trek), who were five and six seconds behind, respectively.
Dennis was the only rider to dip beneath 15 minutes, clocking 14 minutes 56 seconds, while defending champion Vincenzo Nibali was the best-placed of the four overall favourites in 22nd place.
Froome (Team Sky) was seven seconds behind Nibali, clocking 15mins 46secs to place 39th, as the four main contenders for the maillot jaune in Paris on July 26 were separated by 18 seconds.
Ireland's Nicolas Roche finished the stage in 171st place while Dan Martin came in in 95th position.
"It was a tough day for such a short course," 2013 champion Froome said.
"In terms of the GC (general classification) we were all pretty much within a few seconds of each other.
"I would have hoped for a better start (to the time-trial). But I'm pretty happy with that. Certainly I would have taken that at the start of the day.
"It is going to be a long three weeks - this is just the start. I'm happy to have it out the way."
Spaniard Alberto Contador (Tinkoff-Saxo) conceded 15 seconds to Nibali and eight to the Briton in finishing in 15:54.
Nairo Quintana (Movistar) was three seconds further back as his decision to start earlier in the afternoon appeared vindicated.
The lightweight Colombian climber avoided stronger winds which would have hindered his progress.
Froome is more accomplished at longer time-trials, but Saturday's effort against the clock is the only individual time-trial of the race. There is a team time-trial on stage nine.
"Certainly I would have preferred a longer course. I have been training for longer efforts and that would have suited me," Froome added.
Sunday's second stage sees the 198 riders embark on the 166km route from Utrecht to Zelande.
A sprint finish is expected, unless cross winds split the peloton, with Mark Cavendish bidding to add to his 25 Tour stage wins.
Dennis claimed his first Tour stage victory in impressive fashion.
Dutchman Jos van Emden set the early pace in 15:11 but Dennis swiftly overtook him despite trailing at the 7.1km time-check.
Dennis' strong second half of the race was difficult to replicate.
Home favourite Tom Dumoulin (Giant-Alpecin) was anticipated to challenge Dennis, but trailed at the intermediate time check and finished eight seconds behind in fourth place.
Next to step up was multiple world time-trial champion Martin, but, turning a big gear, the German also fell short of Dennis' mark. He later admitted he struggled in the stifling heat.
Martin said: "I'm very very disappointed. I couldn't handle the heat, especially in the second half where I felt weaker."
Martin will now work in support of Cavendish on Sunday.
Cancellara has won an opening time-trial five times at the Tour (four of them prologues), but the Swiss also fell short of Dennis' mark as the Australian triumphed.
"It worked out perfectly. Tour de France yellow jersey - it's a dream," said Dennis, who became the seventh Australian to lead the race.
"I have always wished to be in this position and now I am."
Steve Cummings, riding for African squad MTN Qhubeka in its first Tour, was a surprise best Briton, placing 10th, 32secs behind Dennis.
Geraint Thomas (Team Sky) was 12th, a second further back, and Alex Dowsett (Movistar) three further seconds behind in 13th.
Simon Yates (Orica-GreenEdge) was an impressive 33rd, 46 seconds adrift of Dennis and narrowly behind Nibali, but ahead of Froome, Contador and Quintana.