Steve Bushell incurred the visitors' first caution for a foul on Mark Devlin.

BBC: Northwich 0-2 Halifax

And when referee Mark Clattenburg decided to caution both players, an aggrieved Johnson was none too impressed.

BBC: Birmingham 0-0 Wigan

By the 24th minute, Millwall boss Mark McGhee decided to throw caution to the wind and brought on Republic of Ireland winger Reid for the first time this season.

BBC: Millwall 2-2 Leicester

"There's definitely more caution in the air this time, " said Mark Otto, a Knight Capital Group director based on exchange floor.

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