Chelsea loanees Mason Mount and Fikayo Tomori have been given permission to play for Derby against their parent club at Stamford Bridge in the Carabao Cup on Wednesday.
Could Chelsea regret their decision to allow the pair to play? We take a look at some other times loan players have come back to haunt their parent clubs…
Anderson Talisca joined Besiktas on loan in August 2016 having fallen down the pecking order at Benfica.
Less than a month later the Brazilian returned to the Estadio de Luz for a Champions League match. In the 93rd minute, with Besiktas trailing 1-0, Talisca stepped up and curled a perfect free-kick into the net. It cost his parent club two points.
Talisca didn’t hold back with his celebration which didn’t go down well with Benfica. He was sold to Chinese club Guangzhou Evergrande when his loan deal with Besiktas expired.
Fernando Morientes joined Real Madrid from Zaragoza in the summer of 1997. He formed a formidable partnership with Raul during his formative years at the Bernabeu.
However, Real’s ‘Galactico’ policy soon saw Morientes lost his place to new signing Ronaldo and he made a deadline-day loan move to Monaco in August 2003.
Fast forward nine months and a reunion with Los Blancos was on the cards when the teams met in the Champions League quarter-finals.
With a Galactico-laden Real Madrid team 4-1 up and cruising at the Bernabeu in the first leg, Morientes popped up with a late consolation.
In the second leg, Raul increased Real’s aggregate lead but Ludivic Giuly gave Monaco hope just before half-time. Morientes stepped up with his second goal of the tie early in the second half. Giuly then scored again to give Monaco the advantage on away goals – an advantage they wouldn’t relinquish.
Effectively, Morientes’ away goal had the Bernabeu had won the tie for Monaco and left a lot of red faces in the upper echelons of his parent club.
Thibaut Courtois spent three years on loan at Atletico Madrid from Chelsea. He came up against his parent club in the Champions League semi-finals in 2014.
Courtois’ participation in the tie had been in doubt – Chelsea wanted £5m per game to allow him to play but UEFA overruled them. It would prove to be a fateful decision for Chelsea.
With the tie locked at 1-1, Courtois – according to then-Chelsea boss Jose Mourinho – produced an “impossible” save to deny John Terry. Moments later Diego Costa won and scored a penalty to put Atletico in front. They added a third goal to win the tie 3-1.
Courtois returned to Chelsea a few months later and went on to win two Premier League titles and the FA Cup before joining Real Madrid this summer.
French winger Kingsley Coman joined Bayern on loan from Juventus in August 2015.
The two teams met in the Champions League last-16 later that season. With Bayern trailing 2-1 on the night and 4-3 on aggregate, Coman assisted Thomas Muller’s 91st minute equalizer.
Thiago Alcantara gave Bayern the lead in extra time before Coman added a 4th to seal the win and send his parent club packing.
The following season Bayern exercised their right to buy Coman permanently and he said “Arrivederci” to Juve and Turin.
Premier League loanees aren’t allowed to face their parent clubs because of what happened back in 2004 when Lomana LuaLua joined Portsmouth on loan from Newcastle.
Sir Bobby Robson’s Champions League-chasing Newcastle were 1-0 up at Fratton Park. With stoppage time fast approaching, the ball fell to LuaLua just inside the box. His first-time volley gave Shay Given no chance.
The point proved to be a turning point in Pompey’s season. It lifted them out of the relegation zone and they lost just three of their final 11, finishing 12 points clear of the drop zone. Newcastle finished 5th and missed out on the Champions League.