Porte was tipped as a pre-race favourite but the Team Sky rider struggled with bad luck and crashed heavily on Friday, landing on his knee and hip.

The Tasmanian battled through the individual time trial on Saturday night before losing another 27 minutes to the race leaders on Sunday.

Team Sky’s medical team took the decision to withdraw Porte on Monday, at the second rest day of the three-week race.

‘‘The Giro has been my main goal this year and I’ve worked incredibly hard all season with this in mind,’’ Porte said.

‘‘I’ve had a lot of bad luck this week with the puncture and the time penalty, but it was the crash on Friday that has taken its toll.

‘‘I’m gutted it’s ended this way and that I can’t stay and support Leo, Elia and the team in the last week.

‘‘The plan for me now is to take some time off the bike, get the medical treatment that I need and reset my goals for the rest of the season and come back fighting.’’

Porte went into the Giro as Team Sky’s designated team leader, the first time he had the role for a three-week Grand Tour.

With less than 10km left in stage 10 last week, Porte was in an ideal position at third overall, just 22 seconds behind race leader Alberto Contador.

But he punctured, costing him more than 40 seconds, and controversially was also penalised two minutes for accepting a wheel from Orica-GreenEDGE rider Simon Clarke.

He plummeted to 12th overall, more than three minutes off the pace.

He is expected to be one of Tour de France champion Chris Froome’s key support riders when the Tour gets under way in July.