Race leader Alberto Contador "hopes and trusts" his arm will improve as he bids to win the Giro d'Italia after dislocating his shoulder.
The Spaniard crashed in Thursday's sprint finish but kept his two-second advantage over Italian Fabio Aru after completing Friday's seventh stage, won by home rider Diego Ulissi.
"It was a hard day for me but I'm happy because I got through it," he said.
"After three and-a-half or four hours I didn't know what to do with my arm."
Contador, who won last year's Vuelta a Espana after recovering from a leg fracture at the Tour de France, raced with lower pressure in his tyres to ease the strain on his sore shoulder during the longest stage of this year's race - 264km from Grosseto to Fiuggi.
Team Sky's Richie Porte maintained his third position 20 seconds behind the pink jersey.
Saturday's 186km mountain stage is from Fiuggi to Campitello Matese and Contador added: "It's going to be tough. Normally I'd have been attacking but now it looks like I'll have to defend."
Stage seven result
1 Diego Ulissi (Ita/Lampre-Merida) 7hrs 22mins 21secs,
2 Juan Jose Lobato (Spa/Movistar)
3 Simon Gerrans (Aus/Orica GreenEdge)
4 Manuel Belletti (Ita/Southeast Pro Cycling)
5 Enrico Battaglin (Ita/Bardiani)
General classification after stage seven:
1 Alberto Contador (Spa/Tinkoff-Saxo) at 27hrs 42mins,
2 Fabio Aru (Ita/Astana Pro Team) +2secs
3 Richie Porte (Aus/Team Sky) +20secs
4 Roman Kreuziger (Cze/Tinkoff-Saxo) +22secs
5 Dario Cataldo (Ita/Astana Pro Team) +28secs