Saturday's 3-0 victory over Charlton saw the Championship side keep their 17th clean sheet of the season.
The Owls secured their 17th clean sheet of the campaign in all competitions at the weekend as they beat Charlton 3-0 at Hillsborough, which leaves them just two adrift of the total they managed during the whole of last season.
However, the difference between this term and last year is that Wednesday's resiliency at the back does not appear to be harming the threat they pose in attack. Last season, the Owls were the lowest scoring team of any side that finished above the bottom three, while this season, only league leaders Burnley and Fulham have scored more often than Carlos Carvalhal's men.
Much of that is down to the exciting, free-flowing philosophy that the Portuguese has introduced which has seen goals come from right across the side this season. And after being the benefactor of their style of play against the Addicks - as he opened the scoring - Lees admitted his delight that the defence has been able to maintain its strength while also posing a threat going forward.
"Goals are something I am trying to add to my game. I try and contribute as much as I can. I don't have a goal target. Obviously, clean sheets are the main thing for me. But defenders do need to contribute goals, because that's what successful teams have, centre-halves who chip in," he told the Star.
"Last season, we didn't really score that many goals, but it seems to not be a problem this year."
"We are not too far off the clean-sheet record of last season, which is quite surprising because we do play open, attacking football.
"You associate free-flowing attacking football with being soft, but the boys at the back don't want to lose what we had last season."
The style that they have implemented is surely going to boost their chances of going up to the Premier League this term. While only two of their squad have hit double figures in the league, the fact that the team rank so highly in the goalscoring charts shows that no player in the opposition can switch off as any member of Carvalhal's squad is capable of finding the back of the net.
And with the defence determined to ensure that their expressive football does not leave gaps in behind, it appears that the club have got the balance just right.