The Portuguese side produced a stunning late fightback to snatch a point in Ukraine, courtesy of two late Jackson Martinez goals after Alex Teixeira and Luiz Adriano had given Shakhtar a 2-0 lead with five minutes to play in the Group H clash.
Martinez scored his first from the penalty spot in the 89th minute, with his second coming three minutes into injury time.
"I think the fairest result would be a win, but unfortunately we could not," said the 26-year-old.
"Still, it's an important point that gives us more confidence for the next games.
"We started well, firm and could have scored the penalty we had in our favour.
"We had two defensive errors that ended up giving goals (to Shakhtar), but overall the team has behaved well and let's move on, working to win the next game."
