Jonathan Rea looks destined to be the first man to lift the Superbike World Championship three years in a row after a dominant win in Portugal on Saturday.
The Northern Irishman led from start to finish to take the chequered flag for the 10th time in 19 races this year.
The champion will go into Sunday's second race with a huge 95-point lead over absentee Tom Sykes (injured).
Welshman Chaz Davies recovered from ninth on the grid to take second place behind 30-year-old Rea.
Yorkshire man Sykes, the champion four years ago, was ruled out of both races after dislocating a finger in practice at Portimao.
Sykes remains in second place in the championship standings, but will be overtaken if Davies gets a top-three finish on Sunday.
Winner Rea finished 6.189 seconds ahead of Davies, whose Italian Ducati team-mate Marco Melandri held off England's Leon Camier for third place.
It was a composed ride by Rea in what was his fourth career success at the Portuguese circuit.
He led from fellow Northern Irishman Eugene Laverty off the grid and by halfway had built up a lead of more than five seconds ahead of Davies.
Aprilia rider Laverty ended up in seventh place.
"I made a really good start and built up a lead," said Rea.
"I am really happy with my team - riding the bike is such a pleasure and I'd like to thank them for such a great package."
Race One result (World Superbike Championship round 10, Portimao, Portugal): 1 Jonathan Rea (Gbr) Kawasaki 34mins 38.383secs, 2 Chaz Davies (Gbr) Ducati 34:44.572, 3 Marco Melandri (Ita) Ducati 34:48.549, 4 Leon Camier (Gbr) MV Augusta 34:48.891, 5 Michael van der Mark (Ned) Honda 34:52.122, 6 Jordi Torres (Spa) BMW 34:55.199, 7 Eugene Laverty (Gbr) Aprilia 34:57.169, 8 Lorenzo Savadori (Ita) Aprilia 35:00.473, 9 Javier Fores (Spa) Ducati 35:06.813, 10 Roman Ramos (Spa) Kawasaki 35:17.129.
|2017 WSB Riders' Championship|
|Jonathan Rea (GB)||Kawasaki||406 pts|
|Tom Sykes (GB)||Kawasaki||311|
|Chaz Davies (GB)||Ducati||296|
|Marco Melandri (It)||Ducati||234|
|Alex Lowes (GB)||Yamaha||169|
|Xavi Fores (Sp)||Ducati||153|