Ba made a rare 90-minute appearance in Wednesday night's 1-0 win over Steaua Bucharest which secured top spot in Champions League Group E and set up a potential last-16 draw with Drogba's Galatasaray, one of five teams Chelsea could be paired with on Monday.
But Mourinho could not hide his disappointment at Ba failing to add to his early scrappy goal, despite having a host of chances to do so, including one clear-cut effort early in the second half.
"(Ba) could get more," Mourinho told Chelsea TV.
"He has two goals in the Champions League, which is nice for him. More goals in the Champions League than in the Premier League."
Drogba, who scored 157 goals in 341 Chelsea appearances and whose final act in Chelsea blue was netting the decisive penalty in the 2012 European Cup final win, would have relished tackling Crystal Palace.
The Eagles have been revived somewhat by Tony Pulis' appointment as boss - he has overseen two wins in three games - but their trip to Stamford Bridge will be the most challenging test so far.
The Blues will be determined to flex their Premier League muscles after the loss at Stoke last Saturday and the unconvincing, if entertaining, 4-3 win at Sunderland in the previous fixture.
With an intriguing London derby at Arsenal on December 23, Mourinho's men will be looking to find momentum.
Petr Cech will return in goal after Mark Schwarzer was selected against Steaua, while Mourinho will continue to try to solve both attacking and defensive conundrums.
If the Portuguese is concerned by the strikers' goal return, he should also be alarmed by the defensive frailties which saw Southampton score after 13 seconds in the most recent Premier League match at Stamford Bridge, plus six goals conceded in two games.
Chelsea were also exposed against Steaua, but the Romanians did not have the cutting edge required to take advantage.
Ashley Cole and David Luiz, on their first appearances since the November 2 loss at Newcastle, did little to enhance their claims for a regular place, but may be granted another opportunity against lowly Palace.