Otago was well beaten 49-22 by Wellington on Saturday night, and now has to quickly set its sights on Auckland in its final match at Forsyth Barr Stadium on Thursday.
Results over the weekend mean Otago has qualified for the semifinals of the ITM Cup Championship but it will want to have a home semifinal, at least.
Otago sits on 25 points in second place.
Tasman is five points behind in third place, but has played one game fewer and could get up and pass Otago in the last week of action and secure a home semifinal.
Tasman plays Counties-Manukau in Pukekohe tomorrow night and then faces winless North Harbour in Nelson on Saturday night.
Otago has Auckland on Thursday, its fourth game in 13 days, which is tough going.
The side's energy levels looked low on Saturday night and Brown said the next couple of days were vital for the team to get ready for Auckland.
"This is a big game for us. The Lin Colling Trophy is up for grabs and we want to defend it after winning it last year. The recovery is going to be very important, as a few of the guys are really sore and tired," Brown said.
Brown rejected suggestions of going out to get a bonus point at least, and was fully focused on winning the game.
"We simply just have to concentrate on beating Auckland ... we have just got to more aggressive from minute one to minute 80. At every take of the ball, every lineout, every ruck, we've got to be more aggressive."
Fullback Tony Ensor may be in doubt for the game on Thursday night after he was forced off the field with a shoulder injury on Saturday night.
Prop Tama Tuirirangi is touch-and-go after missing the game on Saturday night.
Otago's scrum had the wobbles at times on Saturday night but Brown had praise for new prop Hisa Sagasa, who made his Otago debut on Saturday night.
Otago felt the effects of three games in eight days on Saturday night, especially with Wellington moving the ball from all over the paddock from the first minute.
"It has been a big eight days for us. We have played some quality footy in that time.
"But they are a good team and we just could not stop the momentum they got going. Once they get on a roll they are very hard to stop.
"If you are not quite there then everything starts going against you. Every ref's call seems to be against you.
Every bounce of the ball seemed to go against us."
Brown could not be too ashamed of his side, for Wellington is top of the table and had plenty of talent on display.
Otago came back into the game in the second half and scrambled well in defence.
It needs to up its energy levels against Auckland, which will have only five days' rest after playing North Harbour yesterday.
