Cape Town - A few former Springboks have expressed concern after the South Africa's stuttering Rugby Championship win over Argentina in Mendoza over the weekend.The Boks scraped through for a 22-17 win, which was a far cry from their 73-13 demolition of the Pumas the previous week in Soweto.Former flank Rob Louw said the Boks need to improve mentally if they are to achieve success in upcoming Tests in Australia and New Zealand."It is very tough to play in unfamiliar conditions. The field there is quite narrow, it looks like a soccer field. Our defence was good at times, but the Springboks will need to improve mentally. The big test against New Zealand still awaits," Louw told Die Burger.Centre and 1995 World Cup winner, Hennie le Roux, also warned that things will be much tougher in Australasia."We were a bit lucky to have won. The coming matches will be different. Australia and New Zealand play a structured game. The winner is the one that can enforce its game plan on the opposition. The Boks must keep their continuity," said Le RouxTwo former Bok props, Hempies du Toit and Ollie le Roux, said while the win was vital in tough conditions, improvement is needed."It was very disappointing to win the one week and then to almost lose the next. I was there in 1982 when we played them there. Too many silly errors were made. It will definitely be different against Australia and New Zealand," said Du Toit."It was a tough win for the Boks. The Argentines made it difficult because they played negative. The Boks also allowed them to get under their skins. We did well in the scrums under the new laws, but there is a lot of room for improvement," said Le Roux.South Africa's next Test in the competition is against Australia in Sydney on September 7.