Cesc Fabregas claims there has not been a "pure striker" better than Diego Costa in recent times and is sorry to see him leave Chelsea for Atletico Madrid.
The Premier League champions last week agreed to sell the Brazil-born Spain international back to Atleti for a fee that could reportedly rise to €60million.
The 28-year-old fell out with Blues boss Antonio Conte last season over rumoured interest from the Chinese Super League, with Costa failing to report back for training ahead of the 2017-18 campaign after being told he was no longer in the Italian's plans.
Chelsea will instead rely on Alvaro Morata, a club-record signing from Real Madrid, for goals as they seek to retain the title.
But Fabregas has made no attempt to disguise his disappointment at losing a friend and valued colleague.
"Clearly, I would have preferred for him to continue as a team-mate," he told Marca. "Diego will never be a rival to me.
"In recent years there has not been a pure striker better than him; he understood my game, read my passes and most importantly he could score from them.
"With Diego, it is not just what he gives you on the pitch but it is his character, too. He brings a lot to the group."
Chelsea visit Atleti in the Champions League on Wednesday, although Costa will not be eligible to play for the club until a FIFA-imposed ban on registering new players ends in January.
"It's a shame for him more than anyone," Fabregas said of the centre-forward's period in self-imposed exile.
"Diego knew that if he signed for Atletico he could not play for a few months.
"It has been a difficult situation for both him and Chelsea; it has been wrong."
|Goerges dashes hopes of all-Russian Kremlin Cup final|
|West Ham 0 Brighton and Hove Albion 3: Murray double piles pressure back on Bilic|
|NBA icon Kobe Bryant meets Neymar and Mbappe on PSG visit|
|Chris Paul to miss Rockets´ home opener with sore knee|
|Dyche not ´running away´ from Burnley as Leicester links intensify|
|UEFA fails to fine Spartak over racist chants in Youth League game|
|Can committed to Liverpool despite contract impasse|
|Albatross helps Luiten maintain narrow Valderrama lead|
|Bernat steps up recovery for Bayern comeback|
|Hasan heroics and Malik might leave Sri Lanka stumped yet again|
|Baker out as Nationals manager|
|Higuain has ´nothing to prove´ despite latest Argentina snub|
|Scotland forward Hardie suspended|
|Suarez struggles no concern for Barca boss Valverde|
|Emery: Neymar needs time to become PSG´s Messi|
|Sarri could have been finance minister! - Spalletti marvels at Napoli boss´ rise|
|Douglas Costa secures Brazil recall for Japan and England friendlies|
|McTominay lands new Manchester United deal|
|Brown blow for Scotland and Glasgow|
|Verstappen signs new Red Bull deal to 2020|
|Rose ready for Spurs return, but won´t start vs Liverpool|
|Koeman confident Everton signings will come good|
|Under-fire Burki lands new four-year Dortmund deal|
|Conte admits to Chelsea midfield crisis ahead of Watford clash|
|Sanchez and Ramsey boost Arsenal for Goodison trip|
|Halep to face Svitolina, Wozniacki and Garcia in Singapore|
|Mane still in rehab, but Klopp won´t block Senegal call-up|
|Kaepernick not blackballed by NFL, claims 49ers owner York|
|Mourinho has ´a feeling´ Ibrahimovic will be back in 2017|
|Conte dismisses Mourinho feud as ´a stupid issue´|
|Always Man City can do better - Guardiola challenges Premier League leaders|
|Aaron Rodgers posts ´comeback starts now´ photo after surgery|
|Klopp anticipating Spurs thriller after Man Utd snoozefest|
|Mawson and Daniels join Mata´s Common Goal|
|Hughes thankful for Stoke stability after ´emotional´ Premier League sackings|
|Bosz determined to turn around Dortmund slump|
|UEFA charge Everton after fans strike Lyon players|
|Adelaide United 2 Melbourne Victory 2: Austin pegs back United after Lia double|
|Webb heartbroken by ´joke´ new Wales selection policy|
|Real Madrid blow as Navas suffers thigh injury|
|Muller close to his old self again, says Heynckes|
|Everton ban fan involved in ugly Lyon scenes|
|Boyd ´very close´ to new Broncos deal|
|British Cycling doctor at centre of ´mystery package´ investigation resigns|
|Manchester City star De Bruyne wants trophies, not awards|
|UEFA charge Roma over alleged racist chanting at Chelsea match|
|Ibrahimovic tipped for December return by training partner Cole|
|Savea replaces injured Todd on All Blacks bench|
|Schweinsteiger ´open to everything´ as he nears end of Chicago Fire contract|
|Ferrari issues have handed Hamilton the title - Button|
|Neymar confirmed wish to leave Barcelona at Messi´s wedding, says Xavi|
|Thomas battles to stay among the leaders as Luke tops the List in Jeju|
|Kershaw jokes he ´might retire´ if Dodgers win World Series|
|Westbrook posts historic triple-double for new-look Thunder|
|Espargaro edges Marquez, Dovizioso in practice|
|Raiders claim exhilarating win over Chiefs|
|Cronk wants to play in 2018, says agent|
|De Bruyne: Man City, United fighting for title|
|Dodgers crush Cubs to reach first World Series since 1988|
|Marshawn Lynch ejected after shoving official|
|WATCH: Hernandez crushes Cubs´ hopes with grand slam|
|Vettel retains F1 title hope|
|LeBron still trying to get into playing shape|
|Wilshere will get Premier League chance – Wenger|
|Giroud: I got lucky with Red Star winner|
|Astros manager Hinch reminds everyone ALCS is not over|
|Lakers coach Walton says players will ´come after´ Lonzo Ball|
|F1 Raceweek: Hamilton dismisses title talk as Alonso eyes future challenge|
|Montella urges fans to ´stand by´ Milan after San Siro boos|
|Koeman admits he could be sacked by Everton|