The reigning world champion was perfectly positioned on the tough final 3km climb in Landerneau, kicking clear of his rival 2km from the line.
As Primož Roglič (Jumbo-Visma) and Tadej Pogačar (UAE Team Emirates) marked each other behind, Alaphilippe (Deceuninck - Quick-Step) continued to power away.
The stage one victory puts Alaphilippe into the yellow jersey.
How it happened
Stage one of the 2021 Tour de France looked to be an explosive course, as the peloton faced a 197km punchy route through Brittany, from Brest to Landerneau.
Tour de France 2021 stage one profile
(Image credit: ASO)
The opening day also featured six classified climbs and countless uncategorised ramps throughout the stage.
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But the most decisive climb was the final ramp in Landerneau, the Côte de la Fosse aux Loups, 3.2km-long at 5.3 per cent average gradient.
A leading group managed to break clear in the opening 30km of the day to set up the day’s breakaway, with Danny Van Poppel (Intermarché-Wanty-Gobert Matériaux, Anthony Perez (Cofidis), Connor Swift (Arkéa-Samsic), Ide Scheling (Bora-Hansgrohe), Cristián Rodríguez (TotalEnergies) and Franck Bonnamour (B&B Hotels p/b KTM).
That leading group pulled out a gap of around 3-40 before the bunch began to reel them back in the opening 100km, with Deceuninck - Quick-Step highly motivated at the head of the peloton.
The racing remained tame in the middle stages, before Schelling kicked off the action with 85km left to race on the way to the summit of the Côte de Stang ar Garront.
As the 23-year-old Dutchman rode away solo, the rest of the break lost their motivation and began to be swept up by the bunch.
With 67km to the line, the remains of the break were caught with Schelling riding out front alone, two minutes ahead of the bunch.
While Schelling’s effort looked doomed, a major crash back in the bunch changed the whole shape of the race.
Just inside 50km, Tony Martin (Jumbo-Visma) went down at speed at the front of the bunch as a spectator stepped into the road to try and get their placard on TV.
Martin hit the placard at full speed and crashed, taking down most of his team and a huge portion of the peloton at the same time.
Most riders were gradually able to get back on their bikes, but the first rider was forced to abandon, as Jasha Sütterlin (Team DSM) wasn’t able to resume his race.
With Deceuninck still leading the bunch, Schelling was finally caught 30km from home as the peloton was almost all together with the decisive final climb on the horizon.
But the race was upset once again by another huge crash inside the final 10km, with Chris Froome (Israel Start-Up Nation) amongst those who came off worst while there were also GC riders caught up in the melee.
Onto the final climb and Deceuninck - Quick-Step continued to dominate the pace, with Julian Alaphilippe the first of the favourites to attack 2km from the summit.
Behind, it was GC favourites Roglič and Pogačar who tried to followed Alaphilippe, marking each other so as not to lose time overall.
Mathieu van der Poel (Alpecin-Fenix) als tried to bridge across, but Alaphilippe was untouchable as he powered up the final climb.
The Frenchman secured the victory eight seconds ahead of Michael Matthews (Team BikeExchange), with Roglic in third.
Alaphilippe also leads overall with 12 seconds over Matthews.
The 2021 Tour de France continues with another punchy stage from Perros-Guirec to Mûr-de-Bretagne Guerledán over 183.5km on stage three.
Tour de France 2021, stage one: Brest to Landerneau (197.8km)
1. Julian Alaphilippe (Fra) Deceuninck - Quick-Step, in 4-39-05
2. Michael Matthews (Aus) Team BikeExchange, at 8 seconds
3. Primož Roglič (Slo) Team Jumbo-Visma
4. Jack Haig (Aus) Bahrain Victorious
5. Wilco Kelderman (Ned) Bora-Hansgrohe
6. Tadej Pogačar (Slo) UAE Team Emirates
7. David Gaudu (Fra) Groupama-FDJ
8. Sergio Higuita (Col) EF Education-Nippo
9. Bauke Mollema (Ned) Trek-Segafredo
10. Geraint Thomas (GBr) Ineos Grenadier, all same time
General classification after stage one
1. Julian Alaphilippe (Fra) Deceuninck - Quick-Step, in 4-39-05
2. Michael Matthews (Aus) Team BikeExchange, at 12 seconds
3. Primož Roglič (Slo) Team Jumbo-Visma, at 14s
4. Jack Haig (Aus) Bahrain Victorious, at 18s
5. Wilco Kelderman (Ned) Bora-Hansgrohe
6. Tadej Pogačar (Slo) UAE Team Emirates
7. David Gaudu (Fra) Groupama-FDJ
8. Sergio Higuita (Col) EF Education-Nippo
9. Bauke Mollema (Ned) Trek-Segafredo
10. Geraint Thomas (GBr) Ineos Grenadier, all same time
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Alex Ballinger is editor of BikeBiz magazine, the leading publication for the UK cycle industry, and is the former digital news editor for CyclingWeekly.com. After gaining experience in local newsrooms, national newspapers and in digital journalism, Alex found his calling in cycling, first as a reporter, then as news editor responsible for Cycling Weekly's online news output, and now as the editor of BikeBiz. Since pro cycling first captured his heart during the 2010 Tour de France (specifically the Contador-Schleck battle) Alex covered three Tours de France, multiple editions of the Tour of Britain, and the World Championships, while both writing and video presenting for Cycling Weekly. He also specialises in fitness writing, often throwing himself into the deep end to help readers improve their own power numbers. Away from the desk, Alex can be found racing time trials, riding BMX and mountain bikes, or exploring off-road on his gravel bike. He’s also an avid gamer, and can usually be found buried in an eclectic selection of books.
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