More to come from Miller in seventh, Sissis 18th at Brno.
The Moto3 FP2 session at the bwin Grand Prix České republiky concluded with Alex Marquez at the head of the timesheet, from Alex Rins and Alexis Masbou.
Marquez (Estrella Galicia 0,0) put in a 2m07.969 lap in the final stages of the session, with his teammate Rins also increasing his pace at the end to finish 0.334s behind in second place. Experienced Frenchman Masbou (Ongetta-Rivacold) trailed P1 by 0.443s in third.
Jakub Kornfeil (Calvo Team) had a similar lap time to Masbou in fourth place whilst Enea Bastianini (Junior Team Go&FUN Moto3) was fifth.
Bastianini had topped the morning FP1 timesheet and was running towards the top in FP2 before a big highside which saw him taken away for medical checks on his right ankle. Bastianini faces a fitness test on Saturday morning having later been diagnosed with a fractured right calcaneus (heel).
The top 10 was completed by Francesco Bagnaia (SKY Racing Team VR46), Jack Miller (Red Bull KTM Ajo), Efren Vazquez (SAXOPRINT RTG), Karel Hanika (Red Bull KTM Ajo) and John McPhee (SAXOPRINT RTG).
Second Australian on the grid Arthur Sissis rode his Mahindra to 18th, 1.697s off the pace of Marquez at the front.
There were also crashes early in the session for Miguel Oliveira (Mahindra Racing) and Juanfran Guevara (Mapfre Aspar Team Moto3) without serious consequence.
2014 MotoGP World Championship
Round 11 – Brno, Czech Republic
Moto3 Friday practice results:
1. Alex MARQUEZ 2m07.969
2. Alex RINS 2m08.303
3. Alexis MASBOU 2m08.412
4. Jakub KORNFEIL 2m08.430
5. Enea BASTIANINI 2m08.529
6. Francesco BAGNAIA 2m08.530
7. Jack MILLER (AUS) 2m08.531
8. Efren VAZQUEZ 2m08.607
9. Karel HANIKA 2m08.813
10. John MCPHEE 2m08.839
18. Arthur SISSIS (AUS) 2m09.666