Former world champion Michal Kwiatkowski claimed the Tirreno-Adriatico week-long race as he retained the overall leader's blue jersey after the final individual time trial on Tuesday.
The Polish beat BMC Racing's Damiano Caruso (Italy) and teammate Gerraint Thomas (Britain) into second and third resepctively on the final general classification.
Poland's Michal Kwiatkowski celebrates on the podium after winning the Tirreno Adriatico cycling race, in San Benedetto del Tronto, Italy, Tuesday, March 13, 2018. "We controlled the race and I'm really happy to be able to win for the team".
Caruso held on to second overall ahead of Team Sky's Geraint Thomas, whose time of 11mins 37 secs earned him a podium place, 32 seconds adrift of his team-mate. When I was warming up it started raining so I was scared something might go wrong.
Although Jos van Emden (LottoNL-Jumbo) came close, the Dutchman had to settle for second place, four seconds behind Dennis's time of 11:14 on the 10.05km course. The Australian, who also won the closing time trial previous year, was four seconds faster than Jos van Emden and eight ahead of Jonathan Castroviejo.
Mads Pedersen (Trek-Segafredo) set an early best time of 11:22, a mark that had him sitting for more than half an hour in the hot seat before Dennis came along and knocked him from the top spot.