The 28-year-old has been approached by Chinese Super League side Tianjin Quanjian over an £80million move.
And while Diego Costa appears to be going nowhere this month, a departure at the end of the season remains a possibility.
Since arriving in west London from Atletico Madrid in 2014, Costa has enjoyed great success at Chelsea, despite the controversy which has followed him.
Antonio Conte has patched up his relationship with the striker, and Ballack believes with another Premier League title in sight, Costa must ignore the lure of more money and continue to ply his trade at the top level.
Diego Costa has excelled at Chelsea but may yet opt to leave the club for China
Players should remember they are playing in a fantastic league in Europe and are top of the top
“It’s up to him with his attitude and his commitment to the club,” Ballack told talkSPORT.
“Because he’s playing for Chelsea and they gave him the possibility to shine and to perform well at one of the biggest clubs in Europe – and he should not forget that.
“Of course, offers are coming with crazy numbers from China, but players should remember they are playing in a fantastic league in Europe and are top of the top, in terms of being watched, the quality of clubs, the players and they are on good money. Nobody would complain about their contracts.
Chelsea fans react to Diego Costa comeback
Sun, January 22, 2017
Click through the gallery for the best reactions as Diego Costa returns for Chelsea
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Click through the gallery for the best reactions to Diego Costa's Chelsea comeback
Michael Ballack won the FA Cup three times and the Premier League once at Chelsea
“It’s a bit of a disturbance to see all these offers coming in, but Costa is professional enough to see what a fantastic club Chelsea is.
“On the other side, each club and each player has to deal with these kinds of situations. What is important; is that they win the league and the next game. Already, he found a good answer last week by coming back and scoring.”
Ballack adored himself to the Chelsea supporters by helping win numerous trophies in his four years at Stamford Bridge.
And with the Blues looking to tie Costa down long-term, he could yet achieve similar feats to the German midfielder.