Five-time world champion Tom Slingsby (AUS) looked determined to banish his demons from Beijing 2008 when a victory and a second place in the Laser class placed him firmly at the top of the leader board on Monday.
The Australian entered the Beijing 2008 Olympic Games as the clear favourite but failed to make the medal race and finished in 22nd place.
On a better start at London 2012 Slingsby said, "Two good starts and two good first beats. I was really happy just to come second (in the first race). It's a lot better than four years ago when I had a couple of 20s on day one. It's all pretty perfect actually."
Guatemalan sailor Juan Ignacio Maegli (GUA) saw off the competition from the favourites to win the first race. Maegli held a commanding lead throughout the race and now lies in second place overall behind Slingsby after an 11th in second place.
2012 Laser World Championship runner up Tonci Stipanovic (CRO) logged consistent results in both of the day's races, placing him in third place on the leader board.
Brazil's Bruno Fontes (BRA) also piled the pressure on the favourites. He finished in second place behind Slingsby in race two to place him eighth overall.
Alejandro Foglia Costa (URU) makes up the trio of South American sailors to finish the first day in the top 10. He finished the second race in third behind FONTES and lies seventh overall.
Lasers resume racing tomorrow at 14:00 local time on the Portland Harbour course.
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