Benfica coach Jorge Jesus rued the disallowing of a goal that denied Jonas a hat-trick and a share of Primeira Liga's golden boot.
Porto's Jackson Martinez (21 goals) was the league's leading scorer, but Jonas - who scored a brace in Benfica's 4-1 win over Maritimo on Saturday - was just behind him with 20.
The Brazilian scored his second at the Estadio da Luz in the 83rd minute, but it would have marked a treble had his 67th-minute effort not been ruled out for an apparent offside.
It was the only mark on Benfica's day - as they were handed the trophy post-match after a resounding victory.
"The first half was more divided, which has to do with the fact that this was a week of celebrations; in the second period, Maritimo 'fell' and we scored more goals," the coach said, as reported by Benfica's website.
"We added another that would give Jonas the scoring title, but the assistant referee saw otherwise.
"It's a pity as Jonas deserved this individual award."
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