Ewan (Lotto-Soudal) rider edged out Arnaud Demare (Groupama–FDJ) after coming off the wheel of Pascal Ackermann (BORA–hansgrohe) to add to his Stage 8 victory.
“Just like yesterday, today’s stage wasn’t too hard to ride," Ewan said. "It takes a little bit out of the legs but compared to some of the other stages, it was still an easy day.
"We did not choose for a full lead-out because we knew there was going to be a headwind sprint. So we decided it would probably be better to come from behind.
"I like to do my sprints like that so it was ideal. My teammates got me into a good position and I really have to thank them for that.”
Mission accomplished, the Australian will pack his bags and leave the Giro to fine-tune his preparations for July's Tour de France.
“I think it makes sense that the sprinters leave the Giro prematurely," Ewan said. "From now on, there are virtually only tough stages left, so not very suited to us.
"I think that the organisation prefers to have to best sprinters at the start. Although they do not finish the Giro, it still guarantees some nice battles in the flat stages.
"I will take some days of rest now and then go on a training camp to prepare for the Tour.”
Stage 10 winner Demare's second place lifted him past Ackermann on the points classification.
Marco Frapporti (Androni Giocattoli-Sidermec), Mirco Maestri (Bardiani-CSF) and Damiano Cima (Nippo Vini Fantini Faizanè) led the break of the day but were caught 25km from the finish.
Valerio Conti (UAE Team Emirates), kept the overall leader's pink jersey before the race heads for the first day in the Alps.
“My goal last winter was to prepare for one-week races and I did well at Vuelta San Juan in Argentina and second at the Tour of Turkey but the third week of the Giro is an unknown for me," he said.
"I’ve never ridden for GC in a Grand Tour. To make the top 10 overall would be an important thing but firstly, I have to defend the Maglia Rosa tomorrow.”
Stage 12 covers 156km between Cuneo and Pinerolo bringing the climbers back into focus for the race.