Four-time Olympic champion Usain Bolt is the huge favourite to win the 200m after defending his 100m title in style on Sunday night.
The 25-year-old won in an Olympic record time of 9.63 seconds and afterwards said he is closer to legendary status.
"This gold means I am one step closer to being a legend so I'm working toward that," he said.
"That's just one step. I have the 200m to go, so I'm looking forward to that."
Bolt won the 200m in Beijing four years ago and holds the world record of 19.19secs.
When asked on BBC Radio 5 live whether he could break the 19-second barrier, he said: "Well, it's been on my mind a couple of years now and this season, on this track, feeling more confident in myself - we'll see.
"I don't want to say I can do it and then not do it. But it's on my mind."
Bolt’s odds for 200m gold were slashed from 1/2 to just 1/5 with bookmakers bet365 on Monday.
bet365 spokesman Steve Freeth told Crunchsports.com: "Despite all the question marks over his fitness and form he was our biggest position of the 2012 Olympics.
"It hardly helps matters when he’s seemingly in every multiple bet going."
Bolt breezed through his 200m heat on Tuesday, with the final taking place at the Olympic Stadium on Thursday at 20:55 BST.