Monte Grappa - Colombia's Nairo Quintana, wearing the leader's pink jersey, has closed in on victory by winning the 19th stage of the Giro d'Italia on the slopes of Monte Grappa on Friday.
Colombian Rigoberto Uran, second in the overall standings, finished third at 1min 26sec, as Quintana achieved his second stage success of this year's race.
Quintana holds a 3min 7sec lead on Uran in the overall standings with Aru at 3min 48sec.
"It was my speciality, I couldn't let this stage go, especially given my family had come from Colombia to watch me," said Quintana.
"I'm delighted to have given them this victory."
Having finished second to Chris Froome at last year's Tour de France, this has been Quintana's opportunity to consolidate his position as the best climber in the world and a Grand Tour contender.
But he refused to be drawn on whether he would challenge for the Tour next season.
"I need to keep improving. Youngsters who like me are from the 1990 generation are very strong.
"Aru, of course, and (Michal) Kwiatkowski, (Rafal) Majka. Our levels are not very far apart.
"Last year the Tour de France gave me the opportunity to show who Nairo Quintana is, to show that I'm able to challenge on a three-week race.
"In this Giro, I've consolidated."
Saturday's final stage in the mountains covers 167km from Maniago to Monte Zoncolan, with the final climb considered one of the toughest in Europe with 10.1km at 11.9 percent gradient.
It is an ideal climb for Quintana to extend his lead, if anything.
"It's a very demanding climb, I like the beginning," said the Colombian.
"I didn't manage to ride the rest of it when we came here for reconnaissance because of the snow.
"I'll control things and if I'm feeling good, I'll try to win the stage."
The main battle is likely to be for the minor places with Aru needing to make up 41sec on Uran to snatch second place while both Rolland and Italian Domenico Pozzovivo perhaps hoping to snatch a podium spot.
However, they are 1min 38sec and 2:28 behind respectively and would need a huge performance on the Zoncolan to move up into the top three.
The time-trial did see a certain amount of movement in the top 10 as 2011 Tour de France winner Cadel Evans climbed two places to seventh with an 11th placed finish.
The Australian had dropped from third to ninth after struggling on Thursday's 18th stage.
Canada's 2012 Giro winner Ryder Hesjedal dropped two places to ninth.
Pozzovivo moved up to fifth after taking more than a minute out of Poland's Rafal Majka, who dropped to sixth.
Results from the 19th stage of the Giro d'Italia, a 26.8km time-trial from Bassano del Grappa to Monte Grappa:
1. Nairo Quintana (COL/MOV) 1hr 05min 37sec(average: 24.5 km/h), 2. Fabio Aru (ITA/AST) at 17sec, 3. Rigoberto Uran (COL/OPQ) 1:26, 4. Pierre Rolland (FRA/EUC) 1:57, 5. Domenico Pozzovivo (ITA/ALM) 2:24, 6. Franco Pellizotti (ITA/AND) 3:22, 7. Rafal Majka (POL/TIN) 3:28, 8. Sebastian Henao (COL/SKY) 3:48, 9. Tim Wellens (BEL/LTB) 4:00, 10. Dario Cataldo (ITA/SKY) 4:10, 11. Cadel Evans (AUS/BMC) 4:26, 12. Stefano Pirazzi (ITA/BAR) 4:34, 13. Riccardo Zoidl (AUT/TRE) 4:42, 14. Edoardo Zardini (ITA/BAR) 4:46, 15. Francis Mourey (FRA/FDJ) 4:46
16. Wilco Kelderman (NED/BKN) 4:52
21. Robert Kiserlovski (CRO/TRE) 5:26
26. Ryder Hesjedal (CAN/GRM) 5:39
47. Ivan Basso (ITA/CAN) 7:12
1. Nairo Quintana (COL/MOV) 79hr 03min 45sec, 2. Rigoberto Uran (COL/OPQ) at 3min 07sec, 3. Fabio Aru (ITA/AST) 3:48, 4. Pierre Rolland (FRA/EUC) 5:26, 5. Domenico Pozzovivo (ITA/ALM) 6:16, 6. Rafal Majka (POL/TIN) 6:59, 7. Cadel Evans (AUS/BMC) 9:25, 8. Wilco Kelderman (NED/BKN) 9:29, 9. Ryder Hesjedal (CAN/GRM) 10:11, 10. Robert Kiserlovski (CRO/TRE) 13:59, 11. Alexis Vuillermoz (FRA/ALM) 22:33, 12. Alexandre Geniez (FRA/FDJ) 24:29, 13. Ivan Basso (ITA/CAN) 28:37, 14. Franco Pellizotti (ITA/AND) 30:26, 15. Maxime Monfort (BEL/LTB) 31:09