Wrexham manager Phil Parkinson has rued his side’s costly mistakes after they suffered a 2-1 defeat to Birmingham City at the Racecourse Ground on Friday night.The match saw Harambee Stars-eligible defender Zak Vyner clock 90 minutes.Download our Mozzart Sport App for more newsVyner, 29, started in his favoured central defensive position as Wrexham suffered their first defeat of the new Championship season.##NAJAVA_MECA_9922034##Birmingham, who had been knocked out of the EFL Cup by Premier League side Brentford in midweek, took the lead in the 13th minute when Phil Neumann rose highest to head home from a corner.Parkinson admitted Wrexham lacked conviction and belief in the final third during the opening half.“The game is won or lost at both ends of the pitch,” Parkinson said.“I’m not bothered about possession – sometimes you have more, sometimes you have less.Some of our approach play was good, but in the first half we didn't play with enough conviction or belief in the final third.”Ingwe 26-27 preview: 7 straight wins, heavy investment and all the ingredients to end lengthy title droughtWrexham responded strongly after the break, with Callum Doyle levelling in the 54th minute after timing his run to meet Lewis O’Brien’s in-swinging cross.Parkinson was pleased with the reaction but felt his side ultimately paid the price for another defensive lapse.“We addressed that at half-time, and I thought we came out really well after the break and looked like the team I want us to be.At the start of the second half we played how I expect us to play, with more belief, more conviction and more drive in the team.”STARS ABROAD: Olunga off the mark for Al Arabi as Kenyan stars feature across EuropeHowever, Neumann restored Birmingham’s lead three minutes after the hour-mark, leaving Parkinson frustrated by two actions in the build-up.“We took responsibility, got back in the game, and that goal just hurts us so much because two actions within that phase of play have cost us.We just can't concede goals like that and expect to win a game of football; it's as simple as that.”Parkinson also reflected on new signing Jacques Ekomié’s full debut, admitting the defender grew into the game but felt Wrexham did not show enough of the belief he demands.##NAJAVA_MECA_9922053##The defeat leaves Wrexham without a win from their opening three Championship matches, following draws against Watford and Cardiff City. The Red Dragons sit 20th with two points.