They have both gone on to become Premier League superstars, but Mohamed Salah and Kevin De Bruyne failed at Chelsea and another former Blues star, Oscar, reckons he knows why.
De Bruyne arrived at Stamford Bridge from Genk in 2012 as a talented prospect, but without too much fanfare as he only cost £7m.
Salah came to west London two years later from Basel, in another relatively low-key deal worth around £11m.
With hindsight it is surprising that neither man made much impact at Chelsea, with the Belgian playing just three times in the league for the Blues and the Egyptian making 13 Premier League appearances.
Both men went on to find success in Europe before De Bruyne returned to the Premier League with Manchester City and Salah moved to Liverpool, developing into two of the finest players on the planet.
While it may seem odd they showed little or nothing of their immense talent at Chelsea, Oscar thinks he knows why.
‘There was a formation where [Eden] Hazard, De Bruyne and I played in midfield and it worked well,’ Oscar told Yellow and Green Football. ‘He only had a few chances, played well but then got injured.
‘I guess that not being consistent at a club that had many options in the centre of the park meant he was not a good fit at the time.
‘With Salah, it was different. He was unstoppable during practice, but always shy and quiet off the field. During the games, I guess he did not have the confidence that we saw at every club he played for after Chelsea, and especially now at Liverpool.
‘Sometimes players don’t feel comfortable with that pressure. I liked it because it made me better.’
Oscar himself enjoyed four impressive seasons at Chelsea after arriving from Internacional in 2012, scoring 38 goals in 203 apeparances.
The Brazilian won two Premier League titles and the Europa League before leaving for Shanghai SIPG in 2017, where he is still playing now at 29-years-old.
The Brazil international arrived at Stamford Bridge with Roberto Di Matteo in charge of the team, but it is Jose Mourinho who he praises for his development in west London.
‘Mourinho helped me a lot and he is one of the best coaches in the world,’ he said. ‘He gives a lot of confidence to his players, but also wants to see them perform at the level of that trust.’
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