Defeated fair and square by the Australian, as they slowed after the finish, runner-up and reigning World Champion Alejandro Valverde (Movistar) reached across to give Matthews a half-hug of congratulations.
Valverde was not the only one to be impressed by the Australian's win, which came after a bad crash in Paris-Nice left Matthews with two fractures in the orbital bone of one eye.
Despite the setbacks, Matthews battled on, claiming his and Team Sunweb's first WorldTour win of the season and the second victory for the team in 2019.
"It was quite difficult today, there was a lot of stress because of the strong winds and we spent a lot of time trying to stay out of trouble," Matthews said afterwards.
"But we took the initiative from the start to try to stay on the front because we knew it was a good stage for me to try to win, whilst I tried to stay protected the whole day."
Matthews said that he could see from the peloton's first lap through the finish at Saint Feliu de Guixols that it was ideal for Valverde, so he put what he called a "big target" on the Spanish veteran to make sure he was close to the rider most likely to prove his rival.
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"He started his sprint quite early, so I could sit on his wheel, then come past with 150 metres to go," Matthews recounted.
"I looked under my arm, saw Valverde was struggling a little bit and that gave me a lot of confidence to go all the way to the line."
"It's my first WorldTour win of the year for me and the team, so after my bad luck in Paris-Nice it's great to be back with a win."
Matthews said after stage 2 that his injuries from his Paris-Nice crash included two fractures in his orbital eye bone, a cut lip, and a chipped tooth. Elsewhere it was reported he had also suffered a concussion.
But he battled back bravely at Milan-San Remo, taking 12th and then endured a tough transfer across to Catalunya on Sunday after flights were delayed at the Nice airport because of a security lockdown for the visit to France by China's Prime Minister.
"I am even more tired today [Monday] than I was yesterday," Matthews told Cyclingnews on Monday morning as he waited for the start of stage 1.
By Tuesday, though, Matthews initial pessimism about his chances of taking a win in the Volta when he was injured and tired had begun to lift.
"It was a really good option to come here. I've often seen the race on TV and saw it was good racing, but this is my first time in this part of the world," he recounted on Tuesday.
"I meant to come here and train a bit, but now we have a win."
