The club's three main forwards, Fernando Torres, Samuel Eto'o and Demba Ba, have managed just four league goals between them this season.
And Blues boss Mourinho has already expressed his frustration at his side's lack of cutting edge in front of goal, which was again apparent in last weekend's 3-2 defeat at Stoke.
That result that meant Mourinho's side slipped to third place in the Premier League table, five points behind leaders Arsenal.
The 1-0 midweek victory over Steaua Bucharest in the Champions League meant Chelsea quickly returned to winning ways and ensured they advanced to the knockout stage of the competition as group winners.
But while Ba's strike was enough to see off Steaua, it was another underwhelming display in front of goal from the Blues and brought a reminder from Mourinho that the Senegal striker must improve his overall return -- a message that could also be directed at Torres and Eto'o.
"He could do better," Mourinho said when asked about Ba. "He got his goal, it's a good feeling for him. He never played in the Champions League before; this is the first season he has played.
"And he has two goals in the Champions League, which is nice for him. More goals in the Champions League than in the Premier League."