Lotterer was under attack from the Mahindra of Rowland, and an optimistic lunge from the Brit into Sainte Devote at the start of lap 19 put the German driver into the wall, with Rowland also ending his own race in the process with damage.
This brought out a safety car, and the incident left Lotterer with a small cut and a pronounced bruise on his left hand - but he explained that there are no other injuries.
For his part, Rowland was adjudged to have been at fault for the incident and receives a three-place grid penalty for the next race in Berlin for causing avoidable contact.
"I saw Rowland sent it on the inside very late so I left space to avoid collision," Lotterer recalled.
"But then he's hit overspeed and went over the kerb, lost the rear and his rear touched my front and sent me straight in the barrier, nothing I could do."
Lotterer explained that the lack of points for Porsche, following Wehrlein's retirement earlier in the race, meant that it was a tough race to swallow.
However, he was optimistic about the pace that the team showed across the Monaco weekend, with both cars making it through to the qualifying duels and exhibiting strong form in the race.
"Yeah, [it hurts] for all of us. I mean, especially for Pascal, he was even more up front. So that's, that's really bitter.
"For me, it was supposed to be good points, in the middle of the race I was fourth, fifth or something, maybe sixth? I don't know.
"For the whole team, obviously quite a tough weekend when you have both cars not scoring points.
"But there's many races left. Lots of positives still, as both cars qualified well, showed good performance. So we're up there. We've just got to put it together like in Mexico, you know, and then we're back on track."
Wehrlein explained his own race-ending problem while he was leading, when his car essentially shut down on him and caused him to pull over on the exit of the tunnel - precipitating a full-course yellow.
He said the race had gone "as planned" until that point, having picked up the lead and looked set to dictate the pace.
"Yeah I lost power, I lost drive, I lost radio communication, the car's just switched off," Wehrlein said.
"[Up to that point] it was really good. The whole race went as planned, it was looking really good. I mean, I was leading the race and I felt strong and yeah. There's not much to say.
"The pace was really good, you never know how the race would turn out, but we were in the best position at that point."
