Few could have imagined the impact Ruben Dias would have on Manchester City following his £62million move from Benfica.
Dias joined City in the wake of their 5-2 defeat at home to Leicester, with Pep Guardiola's dethroned champions in disarray defensively and in need of a strong leader at the back.
Given the unique demands Guardiola places on all of his players and the fact many take time to settle in and adapt to his methods, it was unrealistic to expect Dias to make an immediate difference.
But the 23-year-old defender did just that, ending his debut season as City's Player of the Year, Premier League Player of the Year and the Football Writers' Association Footballer of the Year.
From his commanding debut in a 1-1 draw away to Leeds, where he made a series of vital blocks and interceptions to earn Guardiola's side a precious point, Dias was a natural leader for City.
He filled the huge void left when imperious former skipper Vincent Kompany left City in 2019 after 11 years at the club and, without his signing, Guardiola's side would not have won a third title in four years, as well as the EFL Cup for a fourth successive year and reached a first Champions League final.
The arrival of Dias saw City's defence become more disciplined and solid, with opponents finding it difficult to breach them, with Guardiola's side racking up 21 clean sheets in all competitions.
After being partnered with Aymeric Laporte, Nathan Ake and Eric Garcia in his first few games for City, Dias struck up an immediate and successful partnership and understanding with John Stones, the pair quickly becoming Guardiola's go-to central defensive pairing.
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Despite being the youngest centre-back at Guardiola's disposal - with the exception of Garcia, who was always on the periphery of regular selection - Dias quickly established himself as Guardiola's constant at the back - vocal, demanding, disciplined and always reliable.
He brought consistency and stability to a back line that was open and vulnerable before his arrival, and brought out the best in those defenders around him, in particular Stone, who became a rejuvenated figure alongside him, having lost his way at City.
As well as his physicality and impressive reading of the game, in particular his ability to anticipate threats, rather than react to them, the other aspect of Dias's game that made him such a success under Guardiola was his assuredness in bringing the ball out from the back and starting attacks.
Comfortable in possession, Dias completed more passes than any other Premier League player last season, while his passing accuracy of 94 percent confirmed his assurance on the ball.
If Virgil van Dijk's arrival at Liverpool was the key to them finally winning the title after a 30-year wait, then the same can be said of Dias, who was just as commanding and influential for City.
Without him, City would not have reclaimed their domestic title from Liverpool, the individual accolades that deservedly came his way recognition of his outstanding contribution in his first season in England.