Caleb Ewan holds off the big guns, Tom Dumoulin moves into red

Ewan, the diminutive sprinter from Sydney making his Grand Tour debut, benefited from a textbook lead-out by his team-mates Mat Hayman and Mitchell Docker to gift Orica-GreenEdge their second stage win of the 80th edition of the Vuelta.

At 21 years and 46 days, neo-pro Ewan became the youngest Vuelta stage winner in the past 30 years.

But a bitter-sweet day for the Australian team was completed when overnight leader Esteban Chaves was caught out in a split and lost the leader's red jersey to Dutchman Tom Dumoulin of Giant-Alpecin.

Dumoulin’s team-mate Degenkolb was first to launch his sprint on the ramped finish of the 167km stage from Rota in southern Spain, but the Paris-Roubaix and Milan-San Remo winner was rounded by Ewan inside the final 20m after the road levelled out.

Slovakia's Peter Sagan (Tinkoff-Saxo) was unable to add to his victory in stage three but retained the green points jersey with a solid, if fatigued, third place finish behind Ewan and Degenkolb.

“It’s an incredible feeling. This is by far the biggest victory of my career. When I crossed the line there was so much emotion, I was so happy. It means so much to me to beat two of the best sprinters in the world, on a finish that really suited them,” an ecstatic Ewan told Eurosport after his eleventh win of the season.

“It was super tough out there. My team put me in the best position ahead of the climb. My team-mate [Mitchell Docker] went to the front but I knew it was a little early, so I dropped back a few spots onto Degenkolb’s wheel.

“He went at probably the right time but I waited and waited, and then got over him on the last steep bit. It turned out perfect.”

Luxembourg’s Jean-Pierre Drucker (BMC) took fourth place before a chasing group containing the likes of Dumoulin and Britain’s Chris Froome (Team Sky) was led over the line two seconds down by Spaniard Jose Joaquin Rojas (Movistar).

Spain’s Joaquim Rodriguez (Katusha) led the next group across the line a further six seconds back – with the likes of Colombians Nairo Quintana (Movistar) and Chaves, the overnight race leader, in tow.

Due to the split, Chaves dropped to second place in the overall standings, one second behind Dumoulin. Ireland’s Nicolas Roche (Team Sky) completes the top three, 16 seconds in arrears – with team-mate Froome in seventh at 35 seconds.

One day after his 25th birthday, Ethiopia’s Tsgabu Grmay (Lampre-Merida) soloed clear shortly after the start of the largely pan-flat stage, to be joined 20km later by Belgium’s Iljo Keisse (Etixx-QuickStep) and Canadian Antoine Duchesne (Europcar).

The three riders combined well to eke out a maximum lead of almost seven minutes over the peloton as the sun shone bright in yet another cloudless blue sky.

Back in the pack, the Cofidis team of French sprinter Nacer Bouhanni send one man to the front but the lion’s share of the chase was carried out by the Giant-Alpecin train of John Degenkolb.

With little over 20km remaining – and with the peloton closing the gap to just two minutes – Keisse and Grmay shared some heated words in the break as Duchesne profited by momentarily riding clear.

Track specialist Keisse was clearly upset by the apparent back seat taken by Grmay during the break, and when youngster Duchesne was reeled in, he too had some choice words in store for the first Ethiopian in history to ride the Vuelta.

Keisse danced clear of the bickering pair ahead of the intermediate sprint 18km from the finish, the Belgian managing to hold off the advances of the peloton until being swept up with nine kilometres remaining.

A highly technical final five kilometres included a crude road surface and numerous twists, turns and roundabouts – and it was the Orica-GreenEdge team of eventual winner Ewan who took control of proceedings and led the way.

Through Docker and Hayman, Ewan benefited from a superb lead-out as the peloton was whittled down and separated into numerous splinter groups.

By the time the leaders came to the foot of the final rise to the finish with 500 metres remaining there were just a handful of riders left in it, with Bouhanni among the sprinters distanced on the tricky approach.

Ewan bided his time, waited for Degenkolb to make his move, then showed maturity beyond his years to take the eleventh – and best – win of his season.

While their man Degenkolb missed out on breaking his own Grand Tour duck for the season, Giant-Alpecin had something to celebrate at the end of the day when Dumoulin managed to move onto the race summit.

“It was really not the plan today – my plan was to help John for the sprint – so I was a little bit p***** at the finish,” Dumoulin told Eurosport.

“I didn’t learn about the red jersey until later on so I probably delayed the podium presentation a little because I was on the way to the team bus.

“It’s an unexpected surprise but I’m going to defend the jersey – I’m not giving this up without a fight.”