Wrexham needed all three points to delay celebrations in Birmingham. But after a thoroughly lacklustre outing against a 17th-placed Wigan, their fierce rivals will get their hands on the trophy with six matches to spare.
Moreover, the Red Dragons suffered a mortal blow in their automatic promotion hopes.
It was almost a snooze-fest in the opening 45 minutes as neither of the teams could churn out clear goal-scoring chances. It was a caution-first approach from both managers, and the lack of creativity in attack was simply appalling. Both goalkeepers remained untroubled and the best effort of the half was a 20-yard shot from Dobson.
Parkinson looked vexed with his team's performance as he hurried down the tunnel of The Brick Community Stadium. After the break, the Red Dragons looked more composed as they started weaving together waves of attacks with Oliver Rathbone and Matty James playing a key role in midfield. However, the Welsh side failed to capitalise on their bright spell and soon Wigan regained control.
The match was clamouring for fresh blood and ideas, and Parkinson made a triple change with just over 20 minutes left on the clock as he introduced Steven Fletcher, Ryan Barnett and Elliot Lee. But it did not have the desired effect.
Birmingham are now champions, and Wrexham face an uphill battle to retain their place in the automatic promotion spots.