The Sky Blues fell to a 1-0 defeat against Burton Albion at the Pirelli Stadium during League One action.
A Tom Bayliss own goal proved the difference on the day after an even fought contest away from home.
The goal came from a David Templeton free-kick which found its way past Lee Burge.
Jonson Clarke-Harris and Luke Thomas had chances but it wasn't to be for the Sky Blues.
Despite no goals for either side in the first-half this fixture got off to an expected fast pace.
Templeton came closest inside eight minutes after jinking his way through the City defence but couldn't direct his shot on target.
The Sky Blues then came back with their own attack, however Conor Chaplin couldn't beat Bradley Collins from close range.
Seconds later Albion's keeper saved smartly once again as Tom Bayliss and Thomas linked up well down the right-hand side.
Burge then came up with a couple of vital saves of his own, the first was a low stop to deny Jake Hesketh and minutes later Allen's powerful drive was matched with a strong glove.
Bayliss who'd been lively throughout the first-half surged swiftly through Albion's midfield moments before half-time but couldn't stop his strike from travelling over the crossbar.
Albion started the second period lively and it wasn't long before Templeton drove inside the box, fortunately his curled effort flew inches past City's post.
Chaplin then dug out a cross into Clarke-Harris to open proceedings, however he couldn't direct his header anywhere apart from Collins' gloves.
Clarke-Harris then went through on goal down the left flank, City's frontman though was unable to get a shot on target from a very tight angle.
The Brewers then managed to get the better of the Sky Blues as Templeton whipped in an inswinging free-kick which flicked off the top of Bayliss' head and past Burge.
Abu Ogogo, Amadou Bakayoko and Jodi Jones were all brought on in the latter stages of the game but weren't able to help salvage any points.
Yellows: Kyle McFadzean, Michael Doyle, Stephen Quinn, Abu Ogogo, Amadou Bakayoko.
Goals: O.G. Willis (63')
Burton Albion XI: Bradley Collins, Lucas Akins, John Brayford, Kyle McFadzean, Damien McCrory, Jamie Allen, Stephen Quinn, Scott Fraser, Jake Hesketh (Marcus Harness 90+1'), David Templeton (Will Miller 69'), Devante Cole (Jake Buxton 87').
Unused subs: Stephen Bywater, Joe Sbarra, Elliot Hodge, Kieran Wallace.
Sky Blues XI: Lee Burge (GK), Jack Grimmer, Jordan Willis, Dominic Hyam, Junior Brown, Tom Bayliss, Michael Doyle (C) (Abu Ogogo 72'), Luke Thomas, Jordy Hiwula, Conor Chaplin (Jodi Jones 81'), Jonson Clarke-Harris (Amadou Bakayoko 72').
Unused subs: Corey Addai, Brandon Mason, Jordan Thompson, Liam Kelly.