The tough Tasmanian is used to the rain and knows how to fight for position in a high-speed sprint. Thanks to a perfect lead-out, he was the fastest in the acceleration to the line, beating Manuel Belletti (Ag2r-La Mondiale) and Gerald Ciolek (MTN-Qhubeka).
Mark Cavendish (Omega Pharma-Quick Step) was further back in fifth place, with Andre Greipel (Lotto Belisol) seventh and Peter Sagan (Cannondale Pro Cycling team) a well beaten ninth.
Goss and Orica-GreenEdge have had quiet start to the season but had a perfect day, with Michael Albasini also winning the stage at Paris-Nice.
"I heard right after finish that Albasini won at Paris-Nice. It's a great day for the team," Goss said in the post-race press conference in Indicatore.
"We wanted to do a better [team] time trial yesterday but some days it just doesn’t work out. The guys wanted it today and so it's nice to come away with the win. This is my first road race in Europe this year, so I'm pretty happy how things are going. I'm looking forward to the next few days."
Goss had not won a sprint or a race since stage three of last year's Giro d'Italia to Horsens, the day Roberto Ferrari took out Mark Cavendish at high speed. He finished second eight times last year and was second and fourth in two stages of the Tour Down Under this year.
"It's always nice to win; it doesn’t matter who is second or third," he said when asked if beating Cavendish and Greipel gave him extra satisfaction.
"I didn’t get the upper hand [against Cavendish and Greipel] that many times last year and so it's nice to start off on a winning note this year. I hope it's a year where I can turn a lot of second and third places into wins."
He seems to relish the chaos of high-speed sprinting but shared his success with his teammates, who gave him a great lead-out despite the terrible conditions.
"We had a plan and thought that a good spot to hit the front was at about 1.5km point, at the overpass. We were right where we needed to be. Sagan came from behind me but I knew it was a bit far too go, and so I jumped on his wheel because I knew he wouldn't make it to the finish. I timed my sprint off his."
"I'm pretty happy with the confidence the team has in me. It takes time to build that confidence and know how to do sprints. Look at Lotto, they didn't win in the first year. I guess it's a 12 or 18 month process if you got a team but when you start from scratch it’s a little more difficult. But it’s also a little more satisfying, too, when it works."
A Milano-Sanremo contender
Goss was perhaps a surprise winner of Milano-Sanremo in 2011 but he can handle the late climbs on most races and has the speed to win in a sprint. His win at Tirreno-Adriatico is timely and re-establishes him as one of the favourites for this year's race.
"Sanremo is definitely a goal. It's a race I love," he said.
"I raced it last year but was not my best. I pulled out here and was on antibiotics. I got 15th but I wasn't in good shape. This year the goal is to be in the front group and get a nice result."