It is just as well there is a robust temperament behind Steve Bruce's craggy features, otherwise the Birmingham manager might be totally bemused by the speed with which his team's fortunes have changed.
Apparently on the verge of the sack two weeks ago after a dismal home defeat to Norwich left his team with only two points from a run of five games, he can now reflect that three consecutive Championship wins have put the same group of players in the thick of the promotion race.
They do not yet look like convincing candidates but a first-half goal from the on-loan Arsenal striker Nicklas Bendtner was enough to give them the edge in a frenetic West Midlands derby.
Bruce attributed his side's resurgence to "a few home truths" dispensed at a crisis meeting arranged at his own behest in the wake of the Norwich defeat.
"That was possibly as bad a night as I have had," he said. "I got the players together and a few home truths were spoken. Some of them might have gone under because they did not like what was said but they have pulled together as a group and produced an excellent response."
Birmingham's best players were the two 18-year-olds on loan from Arsenal. Fabrice Muamba was a reliable presence in midfield, winning the ball and using it wisely, while the tall, strong Bendtner confirmed his developing talent with his fifth goal in the Championship and seventh overall.
However, while it was well constructed, it was a goal that should have been prevented as Bendtner's header from Mathew Sadler's cross appeared to have been safely gathered by the goalkeeper Andy Marshall but squirmed away from him and over the line.
The Birmingham defence also looked less than watertight, but Stern John missed several chances and Leon McKenzie hit a post with a header from a cross supplied by the half-time substitute Don Hutchison early in the second half.
That prompted a second half of high-tempo pressure from the home side. Always, however, it was at the risk of conceding again when Birmingham had the opportunity to break out of defence. Bruce reckoned his side "could have scored six" and while that might have been an exaggeration there were certainly clear opportunities for Cameron Jerome, who saw one shot pushed over the bar by Marshall and dragged another wide.
Coventry City (4-4-2): Marshall; Duffy, Page, Ward, Hall; Cameron (Andrews, 77), Hughes (Hutchison, HT), M Doyle, McKenzie; John, Kyle (Adebola, 77). Substitutes not used: Tabb, Clarke.
Birmingham City (4-4-2): Maik Taylor; Kelly, Jaidi, Martin Taylor, Sadler; Danns, Muamba, Clemence, McSheffrey (Campbell 90); Jerome (Larsson 86), Bendtner. Substitutes not used: C Doyle (gk), Gray, Nafti.
Referee: A D'Urso (Essex).Reuse content