The Bahrain-Victorious rider went down hard when a handful of riders hit a traffic island at high speed in the closing kilometres of the sprint stage into Cattolica, leaving him unable to continue the race.
Landa came off worst in the crash, which also involved stage four winner Joe Dombrowski (UAE Team Emirates), and the Spaniard was taken to hospital for treatment.
On Wednesday evening (May 12), Bahrain Victorious confirmed Landa suffered a broken collarbone and multiple rib fractures on his left side.
The 31-year-old general classification hopeful, who shined on the first hilly stage of the race the previous day, was kept in hospital overnight for observation but has remained conscious and “in good spirits” since the crash.
A statement from his team said: “After showing his GC ambitions with the first attack amongst the favourites on stage four, unfortunately, Mikel Landa sustained injuries in a crash on stage five, which will see him no longer take part in the race.
“In the final kilometres of the race, Landa was taken down in a crash involving three other riders after a collision at a traffic island. Landa has been taken to Riccione Hospital, where he is receiving treatment for a broken collarbone and multiple ribs on his left side. Landa will spend the night in the hospital under observation and undergo further investigation.
“Landa remained conscious throughout and is in good spirits to get back on the bike as soon as possible.”
Stage five, a pan-flat and arrow-straight run through the Emilia-Romagna region to the coast, was mostly uneventful until riders entered the finish town of Cattolica, where a number of crashes upset the GC race.
The first rider down was Ineos Grenadiers co-leader Pavel Sivakov, who went down when he was pushed wide and hit a tree at the side of the road.
Sivakov was able to finish the stage, but abandoned the race on Wednesday evening with shoulder injuries.
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