Watch: Jamaica's Shericka Jackson fails to make the 200m semi-finals after easing up at the finishing lineClick here for the complete medal table of the Tokyo Olympic GamesA major blunder by Jamaican sprinter Shericka Jackson saw her women's 200m hope evaporate after she slowed up before the line in Monday's heats and was overtaken by two rivals.Running in the fifth heat, Jackson looked to be heading into the next round but the huge error saw her finish fourth.The 100m bronze medallist failed to look across in the final salvos as Italy's Dalia Kaddari shaded her time to snatch the third automatic semi-final berth."Obviously she misread and she paid the price, Jamaican coach Stephen Francis told The Gleaner newspaper. I expected her to do better but she didnt and I can see why, but she will learn.Jackson, who ran 23.26 seconds, was third-fastest in the world over 200m this year, On Saturday, she won bronze in the blue riband 100m sprint as Jamaica produced a women's clean sweep. Shericka Jackson, pictured top in yellow, slowed down in the final yards of her 200m heat while in second place and ended up in fourth. (BBC screengrab)Shericka Jackson looks stunned after finishing fourth. (Ramsey Cardy/Sportsfile via Getty Images)Elaine Thompson-Herah retained her Olympic title over the distance, her 10.61 seconds victory making her the second-fastest woman ever behind Florence Griffith-Joyner's 10.49 world record in 1988, with Shelly-Ann Fraser-Pryce taking silver.Despite Jackson's blunder, Jamaica will still be the overwhelming favourite to win the womens 4x100m relay.Asked whether Jamaica should be 'given' the gold medal ahead of the final on Friday, Jackson had said: For me, everybody's been talking about the world record and 'Jamaica is going to win'. "First, we need to get the baton around safely."I dont think the focus right now for any of us ladies here is the world record to get the baton around is the most important thing right now. No medallists put down anybody here. Anything can happen.Watch: How to raise an Olympian Cuban-American gymnast Annia Hatch