Fortec driver Rowland had narrowly missed out on pole position for race one, setting a time just 0.018s slower than Carlos Sainz Jr and claiming that he made a mistake on that lap that cost him top spot.
While the Briton was the last car to take the chequered flag in Saturday's session, he was the first on this occasion, but his final time of 1m39.885s was good enough that none of his challengers could beat it as he toured back to the pits.
Rowland's lap deposed Pietro Fantin from first place, after the Brazilian had pipped race one podium finisher Nikolay Martsenko just one minute before that.
The Russian had moved to the top as the first driver to start setting flying laps on his second set of tyres, but by the end of the session he had dropped to 12th.
Rowland's 2013 Formula Renault Eurocup rival Pierre Gasly jumped up to third with his final lap of the session, pushing Will Stevens back down to fourth.
The session still marked a big improvement for Stevens after his Strakka team's difficulties with getting the most out of new tyres had left him down in 15th on the grid for race one.
The top five was completed by championship leader Sainz, who had taken the three previous pole positions this season.
The Spaniard, who admitted after his race one victory that he did not believe Saturday's running was an accurate depiction of the competitive order, was never quite in the thick of the fight for pole, and ended the session half a second adrift of Rowland.
Pos Driver Team Time Gap Laps
1. Oliver Rowland Fortec 1n39.885s 13
2. Pietro Fantin Draco 1n40.054s +0.169s 14
3. Pierre Gasly Arden 1n40.357s +0.472s 13
4. Will Stevens Strakka 1n40.375s +0.490s 13
5. Carlos Sainz Jr. DAMS 1n40.457s +0.572s 14
6. Jazeman Jaafar ISR 1n40.461s +0.576s 13
7. Sergey Sirotkin Fortec 1n40.493s +0.608s 13
8. Luca Ghiotto Draco 1n40.573s +0.688s 12
9. Marco Sorensen Tech 1 1n40.601s +0.716s 13
10. Zoel Amberg AVF 1n40.606s +0.721s 13
11. Matthieu Vaxiviere Lotus 1n40.618s +0.733s 13
12. Nikolay Martsenko Comtec 1n40.630s +0.745s 13
13. William Buller Arden 1n40.643s +0.758s 13
14. Beitske Visser AVF 1n40.749s +0.864s 13
15. Roberto Merhi Zeta Corse 1n40.796s +0.911s 10
16. Marlon Stockinger Lotus 1n40.852s +0.967s 14
17. Norman Nato DAMS 1n40.977s +1.092s 14
18. Oliver Webb Pons 1n40.994s +1.109s 13
19. Matias Laine Strakka 1n41.015s +1.130s 14
20. Meindert van Buuren Pons 1n41.118s +1.233s 14
21. Roman Mavlanov Zeta Corse 1n41.888s +2.003s 11
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