Chelsea manager Thomas Tuchel has lauded new signing Kalidou Koulibaly, praising his quality and personality while claiming that centre-back could become a leader at the club.The Blues signed Koulibaly, 31, from Napoli for a fee of £33 million this summer. On his arrival at Stamford Bridge, the defender received the iconic #26 shirt, which was worn by club legend John Terry.The Englishman played an incredible 715 matches for the west London club and is regarded as one of the greatest centre-backs of all time. Terry won five Premier League titles and one Champions League trophy, among other honors, while leading the club for over 12 years.Since Terry's departure in 2017, the #26 shirt was untouched at the club before it was assigned to Koulibaly.Koulibaly Kalidou@kkoulibaly26 July 15th, 2022Better call…@JohnTerry26 Honored and Proud 🏿#KK @ChelseaFC9732915779📌 July 15th, 2022Better call…@JohnTerry26 💙Honored and Proud 🙏🏿#KK @ChelseaFC https://t.co/uYeVA5y7PLThe Senegalese started his Stamford Bridge career well, keeping a clean sheet against Everton and scoring an exceptional goal against Tottenham Hotspur. However, he was sent off after two yellow card offenses in Chelsea's 3-0 defeat against Leeds United on August 21. Koulibaly will be back for the side's clash away at Southampton on Tuesday, August 30. Speaking at a press conference ahead of the game, Tuchel was all praise for the defender. He said (via Football.london):"He's a fantastic player and has a fantastic personality. I am so happy with what I see, not only that we convinced him to come to the club but how he behaves and trains."He added:"I see a lot of quality and everything that is needed to be a leading figure at Chelsea. He will be on the pitch at Southampton, he is a massive player for us, and there's no doubt about it."Koulibaly played 317 matches for Napoli before his move this summer. Chelsea and Barcelona in talks over Pierre-Emerick AubameyangAs per transfer expert Fabrizio Romano, Chelsea are in negotiations with Barcelona over a potential move for striker Pierre-Emerick Aubameyang.The Gabonese would be open to a move to reunite with his former manager Thomas Tuchel, under whom he played at Borussia Dortmund.The Blues are trying to send left-back Marco Alonso in the other direction as part of the deal but nothing has been finalized yet.Fabrizio Romano@FabrizioRomanoPierre Aubameyang deal. No issues on player side, negotiations are still ongoing between clubs — it wasn’t close to being agreed last week, it’s not off today. #CFCImportant meeting will take place in next 24h to decide how to proceed. Chelsea, insisting to include Alonso.6602651Pierre Aubameyang deal. No issues on player side, negotiations are still ongoing between clubs — it wasn’t close to being agreed last week, it’s not off today. 🚨🔵 #CFCImportant meeting will take place in next 24h to decide how to proceed. Chelsea, insisting to include Alonso. https://t.co/z7FFBs5821Aubameyang, 33, joined Barcelona on a free transfer in January earlier this year and contributed 13 goals in 24 matches. He has also played for Chelsea's London rivals Arsenal, registering 92 goals and 21 assists in 163 matches across all competitions for the Gunners.