Suzuki's Alex Rins topped a damp third MotoGP practice for the Aragon Grand Prix, having been one of only three riders to use slick tyres during the session.
The track was drying out slowly from morning rain at the start of the session, and wet tyres were the preference for almost the entirety of FP3.
The mixed conditions allowed some unusual names to lead early on, with both KTM's Mika Kallio - stepping into replace the ousted Johann Zarco from this weekend to the end of the season - and Suzuki's Joan Mir topping the timesheets for about 10 minutes each.
As the final 15 minutes began, only Fabio Quartararo (Petronas SRT Yamaha) was out on the circuit, with the Frenchman gradually making his way to the top of the order, outpacing Mir by a tenth.
But soon the majority of the field was back on track, and Kallio was again took over top spot with a 1m57.744s, beating Quartararo's time by over a second and forming a KTM one-two with Tech3's Miguel Oliveira at one point.
Kallio couldn't hold onto first place, however, as he was demoted by Vinales, before Rins - who gave slicks a go along with Franco Morbidelli (SRT) and the sister Tech3 bike of Hafizh Syahrin - went another second faster.
Rins ended the session on top with a 1m55.934s, with Vinales and Kallio completing the top three.
Despite topping the session, Rins will still needs to battle through the first part of qualifying after missing the cut at the end of practice on Friday in 11th.
Morbidelli jumped up to fourth at the end on slicks, with Oliveira bringing a second KTM into the top five.
Francesco Bagnaia (Pramac Ducati) and Yamaha's Rossi were sixth and seventh respectively ahead of wildcard Bradley Smith - the only Aprilia to set a laptime in the session.
Aprilia's works riders Aleix Espargaro and Andrea Iannone were two of five riders deciding to forgo a flying lap, joined in doing so by championship leader Marc Marquez (Honda), Jack Miller (Pramac Ducati) and Tito Rabat (Avintia Ducati).
Quartararo and Mir ended up completing the top 10.
|4||Franco Morbidelli||Petronas Yamaha||Yamaha||1m57.988s||2.054s||17|
|5||Miguel Oliveira||Tech3 KTM||KTM||1m58.153s||2.219s||11|
|6||Francesco Bagnaia||Pramac Ducati||Ducati||1m58.159s||2.225s||14|
|9||Fabio Quartararo||Petronas Yamaha||Yamaha||1m58.904s||2.970s||14|
|11||Takaaki Nakagami||LCR Honda||Honda||1m59.143s||3.209s||7|
|15||Hafizh Syahrin||Tech3 KTM||KTM||1m59.610s||3.676s||5|
|17||Cal Crutchlow||LCR Honda||Honda||2m02.673s||6.739s||4|
|18||Karel Abraham||Avintia Ducati||Ducati||2m03.241s||7.307s||6|
|-||Jack Miller||Pramac Ducati||Ducati||-||-||0|
|-||Tito Rabat||Avintia Ducati||Ducati||-||-||0|