Papa Bouba Diop has signed on at Blues for another month.

The free-agent midfielder penned a 28-day contract after showing up well on trial.

It expired at midnight on Saturday and now he has been secured until December 17 for Lee Clark's squad.

Diop, 34, has yet to see Championship action for Blues.

He has been an unused substitute for the last six matches.

Clark is content that the Ravel Morrison-Hayden Mullins partnership in the centre of the park has been functioning.

So Diop has had to make do with a diet of development squad football at Wast Hills so far.

But with a busy period coming up to the turn of the year (and on the horizon is an immediate Saturday, Tuesday, Friday schedule), Diop could finally make his debut.

With Keith Fahey back home in Ireland on indefinite compassionate leave, and Morgaro Gomis not fancied by Clark, the 6ft 5in Senegalese enforcer's importance in the pecking order, and as a different, combative presence for the midfield area, has intensified of late.

Meanwhile, Morrison has the potential to go right to the very top in football says Blues' assistant manager Terry McDermott. The midfielder, who is on loan to Blues for the season, scored his first senior goal in the defeat by Hull.

It's fair to say the 19-year-old has been Blues' most impressive performer since being given an opportunity again by Clark at the end of October.

And according to McDermott, Morrison has what it takes to cut it with the very best.

"He's a great talent," said McDermott, who won 14 trophies including three European Cups with Liverpool between 1974-82.

"He's a great kid and he wants to do well."