The Chilean believes that his side's inability to keep hold of the ball was a key factor in them not being able to pick up all three points at St Mary's
The visitors started ominously and took the lead through Sergio Aguero, threatening to hand the Saints a fourth consecutive loss, but the hosts recovered impressively and capitalised on their majority of possession when Pablo Daniel Osvaldo equalised with a magnificent goal shortly before half-time.
"Southampton played very well but the most important problem that we had was that we lost the ball too easily," Pellegrini told reporters. "Southampton have good players so they could keep it and they tried to play."
Aguero badly scuffed a chance for a second while his side were still leading but the Chilean was reluctant to label that the decisive moment.
"Maybe – 2-0 would have been an important score and, in the first 25 minutes, we played quite well but just one action can't explain this result," he remarked. "After 25 minutes we lost too many balls and that allowed Southampton [back in].
"I think it's a good result for us, a good point, and not a result where we lost two points. I think the draw was a deserved result.
"It was not an easy goal for Osvaldo but it was not the only chance they had. It's not the reason why we haven't got a better result.
"We dropped another point but, maybe, to draw with Southampton here, the way they play, it's normal."
His opposite number, Mauricio Pochettino, felt that the result was a vindication for his side’s persistence during their recent troubles.
"We did well," he enthused. "We've been through a bad run of results but the thing about this team is we keep on believing and we did again [here].
"There have been a few factors in our recent struggles and we've been unfortunate in some of these games but we always try to play the same way and today we beat City on possession, the team with the best possession in the league, so I'm very happy."