The Frenchman brought the ex-Nigeria international to England in the middle of the 1998/99 season, and he highlighted his impact in his debut campaign.
Former Arsenal manager Arsene Wenger has named Nwankwo Kanu as his best signing in the middle of the season during his 22-year spell with the Gunners.
Kanu moved to North London from Inter Milan for a reported £4.15m fee in 1999 and immediately established himself in the team.
He came off the bench to make a significant impact in first few outings for the Gunners with goals against Derby County, Sheffield Wednesday, Tottenham Hotspur and Aston Villa as a substitute.
He also bagged a 15-minute hat-trick against Chelsea in October 1999, which helped Arsenal turn around a two-goal deficit to claim a 3-2 win.
In his first few outings for the Gunners, the ex-Nigeria forward scored 17 goals in 50 matches, and he helped them to a runners-up finish in the Uefa Cup.
When quizzed about the best move he made in January, Wenger picked Kanu – who he described as a huge player – ahead of Pierre-Emerick Aubameyang, whom he signed from Borussia Dortmund for a then club-record fee in January 2018.
“What a difficult question. Over 20 years, maybe Kanu. In the middle of the season. That had a big impact and he was a huge player,” he told beIN Sport.
Kanu was a popular figure at Arsenal during his five-and-a-half years at the club, winning several individual and team laurels before joining West Bromwich Albion in 2004.
He was part of the Invincible team that won the 2003-04 Premier League title without losing a game and also won two FA Cups.
Wenger is currently working as FIFA’s Chief of Global Football Development after leaving Arsenal in 2018.
He disclosed that he is not in favour of the January transfer window, and he thinks it should be scrapped.
“No, I am not. Because I think it is like a race in a marathon where you change the shoes halfway,” he added.
“It is not right, when once you have started the season, you have to finish the season with the same players.
“Or you keep it open the whole season like it was when I arrived in England. They have chosen a rule that is not right.”