The Italian took the victory ahead of Gianni Moscon (Team Sky) with Søren Kragh Andersen (Team Sunweb) in third. Not only is it Trentin’s third win of the race, but also Quick-Step’s fifth.
Most of the general classification contenders came home in a group on the tail of the small selection of sprinters. Chris Froome (Team Sky) finished seventh to retain his overall race lead.
Froome – riding with a heavily bandaged right knee after the previous day’s crashes – maintained his 59-second lead over second-placed Vincenzo Nibali (Bahrain-Merida). Esteban Chaves is third at 2-13.
How it happened
The day’s early break consisted of Arnaud Courteille (FDJ), Thomas De Gendt (Lotto Soudal), Alessandro De Marchi (BMC Racing), Alexis Gougeard (Ag2r-La Mondiale) and Davide Villella (Cannondale-Drapac).
Mountain classification leader Villella scooped up the maximum points on the day’s only classified climb, Alto de Ardales, around 20km from the start in Coín before dropping out of the break and rejoining the peloton to leave four riders out front.
The quartet then worked well together to keep a margin of a few minutes over the peloton. With a rare relatively flat stage on offer, there were several teams interested in pegging back the break and bringing the race back together for a bunch finish.
With 20km to go, the break split apart with De Gendt and De Marchi leading Gougeard and Courteille. De Marchi’s pace was too much for De Gendt, leaving the BMC rider out front solo into the final 10km with a margin of 30 seconds over the chasing bunch.
Katusha-Alpecin, Trek-Segafredo, Bora-Hansgrohe, Quick-Step Floors and Aqua Blue Sport massed at the front of the peloton, upping the speed considerably and De Marchi was reeled in with 7km to go.
Mindful of the tricky run-in to the finish, which featured turns, roundabouts and an uphill section, there was a lot of jostling at the front into the final 5km.
The incline with 3km to go disrupted the rhythm of the peloton, with Bob Jungels doing a great job of keeping Quick-Step and Trentin near the front.
Stage five winner Alexey Lutsenko (Astana) launched a surprise attack after the flamme rouge, but Julian Alaphilippe chased him down for team-mate Trentin, positioning him perfectly after the final corner. Trentin then opened up his sprint with no one able to match his pace as he won with a clear margin.
Moscon was a surprise second, putting in a big sprint to ride past Kragh Andersen.
The GC riders tagged onto the back of the sprinters, with Nibali placing sixth, Froome seventh, Wilco Kelderman (Team Sunweb) eighth and Alberto Contador (Trek-Segafredo), Nicolas Roche (BMC), Steven Kruijswijk (LottoNL-Jumbo), Fabio Aru (Astana), Esteban Chaves (Orica-Scott) and Michael Woods (Cannondale-Drapac) all right behind.
Caught in a split were Ilnur Zakarin (Katusha-Alpecin), David De La Cruz (Quick-Step Floors) and Tejay van Garderen (BMC), all finishing seven seconds adrift of the Froome group. De La Cruz slipped from fourth to fifth overall as a result, changing places with Kelderman.
Although it was calmer than previous days, the stage wasn’t completely without incident. Bert Jan Lindeman (LottoNL-Jumbo) and Jetse Bol (Manzana Postobon) were among those to fall as a result of a crash at the back of the peloton just inside 50km to go. All riders got back on without significant injury.
Dimension Data also lost another rider, as Omar Fraile succumbed to the illness that has been troubling the Spaniard during the race. It leaves the South Africa squad with just three riders.
The 2017 Vuelta a España continues this weekend with a double-header of summit finish stages. Saturday’s 175km trip from Écija finishes atop Sierra de La Pandera, a 12km climb averaging 7.5 per cent gradient. Sunday’s stage 15 is shorter at 129.4km but serves up two first category climbs prior to the finishing ascent to Alto Hoya de la Mora, which includes ramps of up to 22 per cent.
The three-week race concludes in Madrid on Sunday, September 10.
Vuelta a España 2017, stage 13: Coín to Tomares, 198.4km
1. Matteo Trentin (Ita) Quick-Step Floors, in 4-25-13
2. Gianni Moscon (Ita) Team Sky
3. Søren Kragh Andersen (Den) Team Sunweb
4. Michal Schwarzmann (Ger) Bora-Hansgrohe
5. Tom Van Asbroeck (Bel) Cannondale-Drapac
6. Vincenzo Nibali (Ita) Bahrain-Nibali
7. Chris Froome (GBr) Team Sky
8. Wilcom Kelderman (Ned) Team Sunweb
9. Alberto Contador (Esp) Trek-Segafredo
10. Nicolas Roche (Irl) BMC Racing, all same time
11. Steven Kruijswijk (Ned) LottoNl-Jumbo
12. Fabio Aru (Ita) Astana
13. Michael Woods (Can) Cannondale-Drapac
14. Esteban Chaves (Col) Orica-Scott, all same time
General classification after stage 13
1. Christopher Froome (GBr) Team Sky, in 49-22-53
2. Vincenzo Nibali (Ita) Bahrain-Merida, at 59 secs
3. Esteban Chaves (Col) Orica-Scott, at 2-13
4. Wilco Kelderman (Ned) Team Sunweb, at 2-17
5. David De La Cruz (Esp) Quick-Step Floors, at 2-23
6. Ilnur Zakarin (Rus) Katusha-Alpecin, at 2-25
7. Fabio Aru (Ita) Astana Pro Team, at 2-37
8. Michael Woods (Can) Cannondale-Drapac, at 2-41
9. Alberto Contador (Esp) Trek-Segafredo, at 3-13
10. Miguel Angel Lopez (Col) Astana Pro Team, at 3-58