The New Zealand club, currently sitting sixth on the A-League table, are away at Hindmarsh Stadium to the third-placed Reds on Saturday and need a win to really sure up their finals chances.
"For a number of weeks I haven't looked any further ahead than the game at hand, and I'm not changing now," Herbert said.
"We are going into two tough games at venues (Adelaide and Sydney) where we haven't been very successful, if at all, and the first game, against Adelaide, has my full attention."
With the 2010/11 finals series just around the corner, the Phoenix cannot afford to lose any of their three remaining regular season outings, making Manny Muscat and Ben Sigmund's suspensions untimely but Herbert is confident his side can overcome their absence.
"Jade and Dura (Andrew Durante) played together in the centre of defence with Siggy at right back for a period this season so they should be fine," he added.
"With Manny it was disappointing, as it is for any player who is unlucky, and obviously he is a loss, but when we lost Paul Ifill we pulled together and carried on scoring goals.
"We've got a chance of making the finals. It is in our own hands so we have to deal with it."