Toyota's championship leader Rovanpera and M-Sport rival Tanak headed into the event as the overwhelming favourites to challenge for the win on Estonia’s fast gravel roads.
However, an enforced engine change on Tanak’s Ford Puma due to a significant failure following Thursday’s shakedown has effectively put the Estonian out of the victory hunt on home soil before the rally has begun.
WRC sporting regulations allow teams to change engines following shakedown, but in doing so incurs a five-minute penalty.
Rovanpera, who won last year’s visit to Estonia, believes Tanak’s issue and the subsequent penalty has denied him a “proper fight” for victory.
“For sure, it would have been a proper fight with Ott and it is shame when you have this kind of penalty at the start,” Rovanpera told Autosport.
“What can you say? Rules are rules and there have been other drivers that have had the same penalty before. I would say it is a harsh penalty, but what can you do?"
When questioned further on the harshness of the penalty, he added: “There could be penalty that is not so harsh, I don’t know.
“But this has been the penalty for a long time. Others have had it and now Ott has had it not in a good moment. For sure, it is a shame for the fight.”
M-Sport has since completed an engine change on Tanak’s car to allow the 2019 world champion to take the start later this evening.
Tanak has since revealed that he lost a cylinder following his one and only shakedown run, and that the team had told him this morning that it had concerns over his engine.
The issue is even more frustrating for Tanak and the M-Sport team given the extra effort undertaken to prepare for the event that saw the squad contest a national rally in Estonia in addition to a test day.
“It seems like the guys had doubts already yesterday and I was notified this morning as well that we might have something happen and unfortunately something did happen,” Tanak told Autosport.
“For sure, the competition is gone. If this had been at Safari Rally then probably yes [we could salvage something].
“But on a fast rally like this with short and very fast stages we are talking about seconds and tenths of seconds, not minutes.”
