Celtic had to come from behind to maintain their 100% record in the Scottish Premiership with a 2-1 win away at St Mirren on Saturday night.

The Hoops had gone 1-0 down in the first-half after Liam Scales gave away a penalty, only for the defender to equalise from a corner before Hyun-jun Yang netted the winning goal.

Shim Mheuka was unfortunate not to add his first goal for the club to make it three after the referee went to the monitor to subjectively disallow a goal for offside because VAR could not accurately draw lines on the last defender.

It was not the most glamorous of wins for the Hoops, but it was one that was born out of determination and mentality, as best summed up by Hyun-jun Yang's performance.

How Hyun-jun Yang won Celtic the game against St Mirren

The South Korea international scored the winning goal in the match after he raced through to slot underneath the goalkeeper in the 68th minute, securing the three points for the away side.

His goal came after he had already missed multiple big chances to find the back of the net. The most notable one was when Haissem Hassan crossed the ball to the back post and the winger sliced his unmarked effort wide from six yards out.

It was looking like a frustrating evening for Yang, who lost 14 of his 18 duels and only completed two of his nine attempted dribbles, but he kept going and kept going and was eventually rewarded with the goal.

The 24-year-old attacker won the game for Celtic against St Mirren because he has a strong mentality and did not allow mistakes earlier in the match to affect his positive mindset.

Yang kept trying things, despite his struggles in the match, and that paid off when he made a lung-bursting run through the middle and kept his composure to slow away the winning goal.

Celtic have found their best signing since Arne Engels and Matt O'Riley

Speaking of players who keep going no matter what, one of Celtic's other stars on the night is already looking like the club's best signing since Arne Engels and Matt O'Riley.

The Hoops swooped to sign Colombian centre-forward Camilo Duran from Qarabag for a fee of around £5.5m during the summer transfer window to bolster Martin O'Neill's options in the final third.

He has hit the ground running at Parkhead, to say the least, and has already contributed with six goals and three assists in eight appearances in all competitions.

The left-footed number nine was even better than Yang in the win over St Mirren as he proved to be a constant threat at the top end of the pitch, even assisting the winning goal for the South Korean winger with a perfectly weighted pass through the middle of the pitch.

Duran is a rare talent for the Scottish giants because he has the physicality, speed, and technical quality to be a consistent threat at the top end of the pitch, when usually stars only have one or two of those three attributes, such as Benjamin Nygren.

The 24-year-old attacker was unfortunate not to get his name on the scoresheet when his first-half goal was ruled out for an incredibly tight offside that was taken from a dubious point of contact.

Celtic have made millions by selling top players in recent years, selling Engels to West Ham for £22m and O'Riley to Brighton for £25m, but neither of those players combined physicality, speed, and technical quality, as they lacked mobility and explosiveness at times.

Duran has all three of those attributes and looks ready to play at the very top level, as evidenced by his five goals in ten Champions League games for Qarabag, which is why he may be the club's best signing since Engels or O'Riley.

The £5.5m-rated star has already produced three goals and three assists in five matches in the Scottish Premiership, showcasing his ability to be a difference-maker week-in-week-out at Parkhead, and his form could quickly attract attention from Europe's biggest leagues.

Whilst it is down to him to keep up his current form and remain consistent, the early signs are that the Hoops may have hit the jackpot with this signing.