Lucho Gonzales and Steven Defour scored late in each half to give Porto a 2-0 victory over Dinamo Zagreb on Tuesday for a winning start in the Champions League.
This was the seventh consecutive loss for Dinamo Zagreb in the Champions League, after being beaten all six matches in the group stage of the competition last season.
Dinamo Zagreb was dispossessed by Porto early, but there were not many opportunities to score in the first half.
Gonzales gave his team the lead in his 50th Champions League game with an easy finish in the 41st minute after Dinamo goalkeeper Ivan Kelava had deflected a cross from Alex Sandro into his path.
Dinamo was more aggressive in the second half and had two great chances to level. Goalkeeper Helton saved the first instinctively in the 63rd minute from Tonel's bicycle kick.
Helton saved an even better chance for Dinamo in the 78th, stopping a header from Chilean winger Bryan Carrasco.
Porto had a few opportunities from counterattacks before Defour made the game safe in injury time after Christian Atsu had dribbled down the left flank.
