Dejected boss Jos Luhukay was left cursing West Bromwich Albion's "painful" late rally as his Owls side were held to a 2-2 home draw.
First half strikes from Adam Reach and Fernando Forestieri put Wednesday in control and Luhukay's men were on track to move into the Championship play-off opportunities.
However, promotion-chasing WBA struck twice in as many minutes to deny the Owls maximum points.
Luhukay said: "We have a comfortable situation at 2-0 but for West Brom to score two goals so quickly was painful for us. The second goal came from deep in our own half.
"We scored two goals in the first half but we must look at what we can do better. We could talk about their two goals a long time and the team and the players must learn to make the right decisions.
"We could have stopped their two goals in transition. We could have cleared earlier the dangerous moments."
Reach lashed in the opener in the 24th minute, unleashing an unstoppable left foot shot out of Sam Johnstone's reach. It was the midfielder's second goal of the season contenders in six days.
"It was a brilliant goal," conceded Luhukay. "Adam is happy but we wanted the three points.
"We deserved that goal. We played very good in the first half. There was no difference between us and WBA. We had our chances on the ball and we scored the second goal.
"We have not lost at home which is very positive but you want to give your fans and yourself the feeling from winning games. The team gave everything in the 90 minutes but the details in football decide whether you win matches or not.
“We must learn from this as a team. There were some things that could have been done differently in the transitions but we win, draw and lose together.”