Robbie Keane has gone on to become the greatest player to ever represent Republic of Ireland, and although his time at Wolverhampton Wanderers was a huge success and eventually earned the club £6m, we have to limit him to 20th position.
His 88 appearances over the course of two-and-a-bit seasons established himself as one of the biggest prospects in the late nineties. Keane announced himself onto the scene with a double on his debut away at Norwich City and although the goals didn't flow in the 1997-98 campaign, Keane played 47 times in the first team as a 17-year-old, something that would never happen today.
The following season, Keane had scored eight times by the end of September, but that would prove to be half his tally for the season and Wolves would miss out on the playoffs. Despite just eight goals in seven months, Keane was still highly regarded by clubs in the Premier League and it was almost inevitable that he would leave in the summer.
Coventry would win the race for his signature, but only after Keane had began the season with the winning goal in Wolves' First Division opener at Manchester City. He would net the equaliser against Portsmouth on his final appearance at Molineux to end his time at the club on a positive note.