Birmingham City's Paik Seung-ho scored the only goal of the game in a 1-0 Championship win over Oxford United at St Andrew's. The South Korea international midfielder struck five minutes before the interval, breaking the deadlock after a well-worked passing move. Birmingham's Kyogo Furuhashi also had two gilt-edged chances in a dominant opening 45 minutes, but Blues keeper Ryan Allsop pulled off a superb reaction save from Cameron Brannagan's long-range drive midway through. Oxford came out livelier in the second half but lacked potency in front of goal, resulting in their third loss from three games this season. Chris Davies would be satisfied with how Birmingham grew into the game, despite a frantic opening five minutes. Both sides had worthy attempts at goal, with Oxford's Tyler Goodrham curling wide in the opening minute and Ethan Laird guiding a header over from a dangerous free-kick at the other end. The breakthrough finally arrived when Demarai Gray rounded Oxford right-back Hidde ter Avest and cut the ball inside for Paik, who calmly stroked past Jamie Cumming. Lucky to only be 1-0 down, Oxford came out sharper in the second half, with Siriki Dembele finding spaces high up the pitch. Davies's change, introducing Tommy Doyle on 61 minutes in place of a tiring Furuhashi and pushing Jay Stansfield up front, swiftly reasserted Blues' control thanks to the England Under-21 international striker's pressing. Despite spells of Oxford possession, nothing could be fashioned by the U's, highlighting that Birmingham will be hard to beat this season. Birmingham City head coach Chris Davies told BBC Radio WM that he thought it was a strong performance and a very good result for the Blues. Oxford United head coach Gary Rowett said that Birmingham City moved the ball really well and were very good at keeping possession. The win gives Birmingham City a boost in the Championship, with Paik Seung-ho's goal proving to be the decisive factor. The Blues will look to build on this result as they continue their campaign. Birmingham City's next match will be a crucial test of their abilities, as they aim to maintain their strong start to the season.