Joao Almeida shows with a 50-kilometer solo who is the best climber in this Tour of Switzerland

Stage 4 of the Tour de Suisse started in Heiden, where Quinn Simmons (Lidl-Trek) had impressively won Stage 3 the day before. From the town on Lake Constance, the route headed straight south, finishing in the Italian town of Borgonuovo di Piuro.

The riders set off with one less man, as Geraint Thomas decided not to start as a precaution following his crash on Day 3. The Welshman was dealing with pain in his knee and hamstring, and opted to focus on full recovery ahead of the main goal of his final season as a pro: the Tour de France.

With a flat opening phase of 100 kilometers in what has so far been a chaotic Tour de Suisse, the riders knew exactly what to expect: attack, attack, and attack again. From the very start, there was a barrage of breakaway attempts, with Neilson Powless (EF) among those repeatedly on the offensive. Actually getting away, however, was a different story.

The peloton was riding at extremely high speeds in the opening hours. The first 80 kilometers were completed at a staggering average speed of 54 (!) kilometers per hour, making it clear why it was so difficult for anyone to build a lead.

At 106 kilometers from the finish, after Laurens De Plus (INEOS Grenadiers) also abandoned following Geraint Thomas—there was finally a split. Eight riders got away, including Powless and once again Simmons. Also in the move: Thomas Gloag (Visma | Lease a Bike), AJ August (INEOS), Georg Zimmermann (Intermarché-Wanty), Sébastien Grignard (Lotto), Marius Mayrhofer, and Larry Warbasse of Tudor.

Approaching the base of the Splügen Pass, the only categorized climb of the day at 8.8 kilometers with an average gradient of 7.3%, the front group already began to break apart. The first four mentioned riders remained, but UAE Emirates-XRG wasn’t giving them much breathing room in the peloton either. As a result, the riders were racing 45 minutes faster than the fastest predicted schedule, showing just how intense the pace was.

By the time they hit the Splügen Pass, the breakaway's lead had shrunk to just thirty seconds, and UAE’s Felix Grossschartner and Jan Christen quickly erased what was left of it. This left a group of about fifteen climbers, including most of the top names.

Almeida launched an attack four kilometers from the summit, dropping the favorites one by one. Bart Lemmen (Visma | Lease a Bike) and race leader Grégoire were the first to be dropped, followed by second-placed Kévin Vauquelin (Arkéa - B&B Hotels). Ben O'Connor (Jayco AlUla) couldn’t hold on either, and eventually even the last two to remain, Decathlon AG2R climber Felix Gall and Picnic PostNL’s Oscar Onley, had to let go.

Almeida eventually reached the summit with a 45-second lead over his closest chasers, where things began to regroup a bit. Grégoire, meanwhile, lost a minute and a half and was forced to chase, but thanks to his strong descending skills, he managed to catch up. He bridged to the group of other general classification contenders.

The final fourteen kilometers were a slight uphill drag, which Almeida began with a lead of forty seconds. The Portuguese rider managed to hold on to that gap, although Grégoire and company still have a solid advantage in the overall standings. Onley finished second, ahead of O'Connor, Grégoire, and Vauquelin.