The British No 1 was behind from the first game when she was broken by the Latvian and simply could not get back into the first set.
She lost her serve in the third game of the second set but managed to break back for 3-3. However, frustratingly for her she then handed over another break, which proved decisive.
Tokyo 2020
'Djokovic couldn't control his emotions' - 'Frustration boiled over' with racket abuse in loss
AN HOUR AGO
Ostapenko the French Open champion will now face Margarita Gasparyan or Petra Martic in the next round.
Tokyo 2020
'Heartbreaking for his partner' - Djokovic pulls out of mixed doubles after singles defeat
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Tokyo 2020
'Wonderful moment' - Djokovic misses out on medal as Carreno Busta wins bronze
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