Smith was unable to finish in the top three in Misano.
Oxfordshire's Bradley Smith narrowly missed out on a podium after finishing in fourth place in the 125cc Grand Prix in San Marino.
The 19-year old started in pole position after outpacing Marc Marquez and Nico Terol in qualifying.
Spaniard Marquez took the chequered flag first ahead of Terol to maintain his lead in the championship.
Efren Vazquez completed an all-Spanish top three by beating Smith to third place in Misano.
The whole event was overshadowed by the tragic death of Shoya Tomizawa.
The Japanese rider passed away in hospital after a heavy crash during the Moto2 race.