Oh Hyeon-gyu makes brief appearance as Celtic beat St. Johnstone 4-1

Celtic made short work of St. Johnstone on Sunday to hold on to their nine-point lead at the top of the Scottish Premiership.

Celtic's Kyogo Furuhashi celebrates scoring his side's second goal during a Scottish Premiership match against St. Johnstone at McDiarmid Park in Perth, Scotland on Sunday. [AP/YONHAP]

Celtic made short work of St. Johnstone on Sunday to hold on to their nine-point lead at the top of the Scottish Premiership.

An early own goal from Andrew Considine kicked off the rout, with Kyogo Furuhashi and Aaron Mooy each adding one of their own before the end of the first half. Drey Wright got one back for the home side, but the visitors were still up 3-1 at the break.

Korean midfielder Oh Hyeon-gyu came on in the 79th minute for Furuhashi and played an unexpectedly important role in the final frame of the game when Considine got a red card for a hard foul on Oh and David Turnbull scored the resulting free kick.

The end result was a dominant 4-1 win for Celtic with the 10 remaining men of St. Johnstone left with their fourth loss in the last five games.

Oh signed with Celtic on Jan. 25 in a deal reportedly valued at £2.5 million ($3-million) after a drawn-out transfer saga that saw the Scottish club’s offer initially rejected before both Oh and the Bluewings manager made it clear they thought he deserved the opportunity.

Oh scored 14 goals in 39 appearances across all competitions in the 2022 K League season. He was called up to the senior Korean squad for the first time on Nov. 11, playing 18 minutes of a friendly against Iceland, and landing on the reserves list for the 2022 Qatar World Cup.

The snappy Korean midfielder is still finding his feet in Glasgow, appearing in all three games since his arrival but only ever for less than 20 minutes at the end of the second half. With such a strong squad to choose from, Celtic manager Ange Postecoglou told reporters Sunday he’s focused on rotating his players to best handle a busy schedule.

“Some really good players didn't get on the pitch today and some really good players didn't get in the squad," Postecoglou said after the game.

"For about four or five weeks now we have a game a week so that gives us the chance to work really hard at training and get everyone up another level, another notch, and increase our performance both on an individual and collective basis.

"We have set our mark as always trying to finish stronger than we started and we are well on the way to that. "We are definitely getting stronger every week and that's what we want to do till the end of the year.”

BY JIM BULLEY [jim.bulley@joongang.co.kr]