The Yorkshireman had just missed out on a spot in Sunday's qualifying duels, ultimately starting 10th ahead of team-mate Alexander Sims - who had made the final on Saturday.
Mahindra had been a presence among the frontrunners across practice, and Rowland put that newly extracted pace to good use in his rise through the field in the second race.
Having charged up to fifth as he sought to be the best non-Mercedes runner in race two, Rowland found himself slightly short on energy in the closing stages and dropped two places to Antonio Felix da Costa and Robin Frijns - but was able to hold off Andre Lotterer.
"I'm happy. I mean, sometimes you finish seventh with a bit of luck," Rowland explained.
"But I think today we had really good pace and we came from behind.
"It's nice to see actually, eventually having a bit of luck and just everything going well.
"I think everybody's worked quite hard to get to where we are. We still have a lot of work ahead. But it was a nice race and I enjoyed it."
Rowland explained his late-race drop, citing that his relative lack of knowledge of the Mahindra systems in that scenario had led him to initially underconsume energy, before subsequently overconsuming after losing the slipstream when up in fifth.
"It was my fault," he conceded. But yeah, I'm a bit inexperienced with my systems and I was under consuming in the slipstream.
"And then as soon as I passed, I then overconsumed for two laps, and I killed my target, basically.
"Had I been a bit more controlled when I passed Antonio I would have finished fifth I think. It was just a bit of experience and understanding, because obviously in the slipstream you save quite a lot of energy.
"It was also understanding how much energy that was. Because when my beeps come at the same point and you don't have a slipstream, then you waste energy.
"But fifth or seventh, I don't really care. I'm happy with the race."
Rowland explained that changes Mahindra had made to software, having arrived in Monaco with braking updates and then bringing more tweaks to Berlin, had showed signs of paying off.
He added that Sims' qualifying performance on Saturday had shown the fruits of the team's labour, a result that Rowland was happy to see.
"It's nice to see that the direction we're both pushing in, and the things that we want [from the car] are making a difference," he said.
"Yesterday, what we saw with Simsy in qualifying, it's also nice to see from my perspective. Some people might not like that when their team-mate does well!
"But the things that we're doing and understanding are making a difference, and to do a race like that in this track is not easy. So with what we did today, I think we have to take a lot of positives."
