Erling Braut Haaland's autograph will be one of the most coveted this summer, but one enthusiastic referee's assistant has beaten some of Europe's biggest clubs to the 20 year old's signature. After Borussia Dortmund's 2-1 defeat to Manchester City in the Champions League quarter-final first leg on Tuesday, Octavian Sovre, one of the Romanian assistant referees, followed Haaland down the tunnel at Etihad Stadium and appeared to get him to sign a red and yellow card he produced from his top pocket. "Maybe he's a fan of Haaland," said City manager Pep Guardiola. "Maybe it was for his son or daughter." "I've never seen it before, but the referee and the linesman were correct, they did a good job. That's all." Haaland is wanted by a host of clubs, including City and Spanish giants Barcelona and Real Madrid. He failed to add to his 10 Champions League goals already this season against City, but did set up Marco Reus for the Germans' vital away goal. However, goals from Kevin de Bruyne and Phil Foden gave City a slender advantage heading into next week's second leg. The Romanian officials were also involved in a couple of controversial incidents during the match. City had a penalty overturned after a VAR review, while Dortmund's Jude Bellingham saw a first-half goal harshly ruled out for raising his boot to beat Ederson to the ball. However, Guardiola defended their performance. "The referees were brilliant. The game was not a problem. "It was a penalty and after they saw on VAR it was not. After with Bellingham the action from the leg is higher than expected. "The referees and the linesmen were correct so it was perfect." This is not the first time the conduct of Sovre or Romanian officials has been called into question this season. The match officials was also reprimanded for "inappropriate behaviour" by Uefa after a Champions League group game between Paris Saint-Germain and Istanbul Basaksehir was postponed in December. The match was suspended for 24 hours after <a href="https://www.thenationalnews.com/sport/psg-v-istanbul-basaksehir-postponed-after-players-walk-off-over-alleged-racism-1.1125220">allegations of racism</a> against fourth official Sebastian Coltescu. Coltescu was accused of describing Basaksehir's Cameroonian assistant coach Pierre Webo as "black", or "negru" in Romanian. Uefa cleared Coltescu of racism but he was banned from officiating for the rest of the season. Coltescu and Sovre were also ordered to attend an educational programme.