Alex McLeish used just one man up front against Bolton - but the defensive tactic backfired as his side conceded twice at Villa Park.
The Scot won the Carling Cup final last season using that very ploy with Birmingham City but Chris Eagles and Gael Kakuta exposed its shortcomings in the second half.
Rough and tumble: Aston Villa midfielder Stiliyan Petrov fouls Bolton's Darren Pratley (left)
MATCH FACTS Aston Villa: Given, Hutton, Collins, Dunne, Warnock, Albrighton, Petrov, Ireland, Bannan, Agbonlahor, Delfouneso. Subs not used: Guzan, N'Zogbia, Delph, Beye, Lowry, Gardner, Burke.
Bolton: Bogdan, Steinsson, Cahill, Wheater, Gardner, Eagles, Holden, Muamba, Pratley, Kakuta, Ngog. Subs not used: Jaaskelainen, Robinson, Sanli, Petrov, Kevin Davies, Mark Davies, Blake.
Referee: Darren Deadman
Despite overhauling the team that wasdefeated by Norwich City last Saturday, Bolton looked more coherent anddeserved the opening goal 10 minutes into the second half.
A long cross-field pass was touched into Eagles' path by Marc Albrighton as Villa's winger attempted to cut out the danger. But it gifted the midfielder a sight of goal and the summer signing from Burnley stepped inside Alan Hutton before curling a shot beyond Shay Given.
It was no more than Bolton deserved as Villa looked ill-at-ease as Gabby Agbonlahor struggled manfully to make any headway.
An injury to Darren Bent in part forced McLeish's hand but he decided to use Nathan Delfouneso in a wide position on the left as Villa struggled.
One of the wholesale alterations made by Coyle was to bring Stuart Holden back into his midfield.
Tussle: Stephen Warnock battles with Gael Kakuta (right)
The American has been sorely missed by Bolton since rupturing his knee ligaments six months ago and his presence was a calming influence.
Indeed, up until the final quarter, Villa still had not forced Adam Bogdan into a save in front of a home crowd that was growing increasingly impatient.
Kakuta, the 20-year-old on loan from Chelsea, then added to their woes. He collected a free-kick that was missed by James Collins and Kevin Davies and fired into the bottom right corner after 78 minutes.
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