Blues coach Tana Umaga has admitted that poor discipline may cost them crucial points in their match against the Chiefs tonight.

Umaga says they have shown a lot of heart but giving away penalties can cost you a win.

He is expecting a clinical performance from his players tonight.

The former All Blacks captain says they have been working hard on their defence as they expect a dangerous attacking Chiefs team tonight.

The Chiefs will face the Blues at 7.35 tonight while Crusaders face the Western Force at 11pm.

The Hurricanes play the Jaguares at 7.35pm tomorrow while the Highlanders play the Reds at 9.40pm.