Rea led home Kawasaki team-mate and fellow Brit Tom Sykes by 0.222 seconds after a thrilling duel between the two, with Michael Van Der Mark coming in third, nine seconds distant.
Defending champion Rea's victory means that he has won all three races of the season so far, and he was delighted to have won a tough battle on a day when the Northern Irishman admitted that he struggled with his bike.

Rea delighted to win in Thailand: 'I honestly emptied my tank in that race'

Thailand
Rea denied by Sykes in Thailand
13/03/2016 AT 17:55
Race two takes place at 9am GMT on Sunday.

Jonathan Rea claims race one in Thailand

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RESULTS

1. Jonathan Rea GBR Kawasaki Racing ZX-10R 20 laps
2. Tom Sykes GBR Kawasaki Racing ZX-10R +0.222
3. Michael van der Mark NED Honda Racing CBR1000RR +9.623
4. Chaz Davies GBR Aruba.it Racing Ducati 1199R +17.167
5. Markus Reiterberger GER Althea BMW S1000RR +18.894
6. Alex Lowes GBR PATA Crescent Yamaha R1 +20.754
7. Sylvain Guintoli FRA PATA Crescent Yamaha R1 +24.221
8. Jordi Torres ESP Althea BMW S1000RR +31.064
9. Alex de Angelis RSM IodaRacing Aprilia RSV4 +34.348
10. Lorenzo Savadori ITA IodaRacing Aprilia RSV4 +34.479
Thailand
Rea reigns in Thailand
12/03/2016 AT 18:58
Thailand
Rea delighted to win in Thailand: 'I honestly emptied my tank in that race'
12/03/2016 AT 11:30