Calado topped the timesheets after the chequered flag fell with a lap of 3m30.113s at the wheel of the #51 499P Le Mans Hypercar he shares with Alessandro Pier Guidi and Antonio Giovinazzi.
That was enough to beat the pole-sitting #50 car, in which Nielsen set a best effort of 3m32.959s, by a comfortable 2.8 seconds.
Best of the rest behind the Ferrari LMHs was the best of the Cadillac V-Series.R LMDhs, the #3 car in which Sebastien Bourdais suffered a dramatic fire in Thursday evening’s Hyperpole session.
Bourdais slotted into third at the very end of the session on a 3m33.255s to demote the leading Peugeot 9X8, the #94 car of Nico Muller, to fourth ahead of the two Toyota GR010 HYBRIDs of Mike Conway and Sebastien Buemi.
Porsche’s top representative was Andre Lotterer in seventh place aboard the #6 963 LMDh, followed by Paul di Resta in the #93 Peugeot.
Numerous Hypercars did not set flying laps, including the #2 Cadillac, #5 and #75 Porsches, the Action Express-entered #311 Caddy and the customer Jota Porsche.
The quickest LMP2 in ninth overall was the #23 United Autosports ORECA in which Tom Blomqvist posted a 3m39.818s.
Second-fastest was the #34 Inter Europol Competition machine of Fabio Scherer, 1.2 seconds behind, followed by Mathias Beche in the #14 Nielsen Racing car.
Leading the way in GTE Am were a pair of Kessel Racing-entered Ferrari 488 GTEs, with Daniel Serra setting the pace in the CarGuy Racing-branded #57 car ahead of Kei Cozzolino in the #74 machine.
The Garage 56 NASCAR Cup car posted a best of 3m59.403s in the hands of Mike Rockenfeller, behind the fastest six GTE cars.
The 100th anniversary running of the Le Mans 24 Hours is slated to begin at 16:00 local time.
