Espargaro brothers Aleix and Pol were first and second on the final day of 2014 pre-season MotoGP testing, but the latter ended the session with a broken collarbone.
The younger Espargaro sustained the injury in a late crash at Turn 6.
He will fly to Barcelona for surgery on Monday, 10 days before practice begins for the season-opening Qatar Grand Prix back at the Losail track.
Aleix Espargaro was just 0.033 seconds quicker than his brother as he set the overall pace on Forward Racing's Open class Yamaha for the second time in three days.
Both Tech 3 bikes were in the top three, with Bradley Smith third. The Briton also had a crash, as did satellite Honda riders Stefan Bradl (twice) and Alvaro Bautista, plus Avintia's Hector Barbera. All were unhurt.
Prior to their incidents, Bradl and Saturday pacesetter Bautista had already set times good enough for fourth and fifth, ahead of Andrea Iannone on the fastest Ducati.
The factory Yamaha, Honda and Ducati teams all sat out the Qatar test as they had run in Bridgestone's Phillip Island sessions earlier in the week.
Pos Rider Team/Bike Time Gap Laps 1. Aleix Espargaro Forward-Yamaha 1m54.874s 47 2. Pol Espargaro Tech 3 Yamaha 1m54.907s +0.033s 45 3. Bradley Smith Tech 3 Yamaha 1m55.027s +0.153s 55 4. Stefan Bradl LCR Honda 1m55.187s +0.313s 40 5. Alvaro Bautista Gresini Honda 1m55.232s +0.358s 50 6. Andrea Iannone Pramac Ducati 1m55.518s +0.644s 59 7. Colin Edwards Forward-Yamaha 1m55.978s +1.104s 31 8. Yonny Hernandez Pramac Ducati 1m56.056s +1.182s 47 9. Nicky Hayden Aspar Honda 1m56.273s +1.399s 44 10. Hiroshi Aoyama Aspar Honda 1m57.006s +2.132s 56 11. Scott Redding Gresini Honda 1m57.009s +2.135s 50 12. Hector Barbera Avintia FTR-Kawasaki 1m57.142s +2.268s 38 13. Karel Abraham Cardion Honda 1m57.342 +2.468s 34 14. Mike di Meglio Avintia FTR-Kawasaki 1m57.669s +2.795s 44 15. Danilo Petrucci Ioda Aprilia 1m58.086s +3.212s 55 16. Michael Laverty PBM Aprilia 1m58.555s +3.681s 30 17. Broc Parkes PBM Aprilia 1m58.971s +4.097s 20