Marseille won 2-1 at the Stade Velodrome thanks to goals from Nicolas N'Koulou and Florian Thauvin but Bielsa was left frustrated by the way the home side faded away in both halves of the Ligue 1 clash.
While the win saw Marseille regain their four-point lead over reigning champions Paris Saint-Germain, Bielsa was unhappy.
"The team played the beginning of each half and then lost its features," the Argentine said at his post-match media conference.
"After the first goal, we lost our mobility and consistent pressing on the opponent. After the second goal, the same thing happened to a lesser degree.
"After the expulsion [of Alaixys Romao in the 76th minute], the team has struggled to keep its balance."
The win was Marseille's first in three games, after they fell to Lyon in the league in October and were dumped out of the Coupe de la Ligue by Rennes on Wednesday.
But while the result was the right one for the south coast club, Bielsa argued he was happier with his side's display in their 1-0 loss to Lyon, as he prepares for Le Classique against PSG next week.
"The match against Lyon was the best game we have played this season," he said.
"Tonight's game was not good, teams are judged on what they are capable of doing.
"I know the mistakes we have made but I know perfectly the qualities of my team and I know what they are capable of doing."
Meanwhile, Bielsa said defenders Baptiste Aloe and Gael Andonian had been put on the bench ahead of Doria and Stephane Sparagna because they were "in better shape".
Doria has yet to play for Marseille since signing from Botafogo in the lead-up to the 2014-15 campaign, with Bielsa refusing to pick the Brazilian central defender because he wanted to sign Toby Alderweireld instead.
"I had to choose between Sparagna and Aloe and between Doria and Andonian," the 59-year-old said.
"I took Aloe and Andonian because there is virtually no difference in age. In addition, I took the most in-form players in the knowledge that in all decisions, I could be wrong.
"Aloe is in better shape than Doria and Andonian is in better shape than Sparagna."
