Winger Riyad Mahrez has missed three of his last four penalties for Manchester City in all competitions.
City sealed the top spot in Group G of the Champions League after gaining a point against Dortmund in Germany.
Manchester City manager Pep Guardiola insists that his Cityzens 'must improve' their penalty outcome in the Champions League after he saw another miss from the spot against Borussia Dortmund.
Riyad Mahrez was fouled by midfielder Emre Can, and the City winger stepped up himself but goalkeeper Gregor Kobel dived the right way to save his spot-kick, meaning the Algeria international has missed three of his last four penalties in all competitions for the Cityzens.
Both sides played out a goalless draw at the Signal Iduna Park and qualified for the knockout stages, regardless, City secured the top spot of Group G in Europe's elite competition.
And Guardiola, who surprisingly replaced top scorer Erling Haaland at half-time, told BT Sport he was happy with how his team managed the second half compared to how they played in the first-half in which they conceded several counterattacks
'A problem we have to improve.'
"We managed the second half, and in the first half we conceded some counter-attacks - they are so fast. We suffered as a team, the game on Saturday was so tiring," the Spaniard said.
"It's what we wanted, top of the group, and we will be in the last 16 next time, so really good. Dortmund did not want to press high, so we adjusted a bit, our pressing. In the first half, we had problems down the left side. Apparently, they thought a draw was good for them and for us as well."
On taking off Erling Haaland, who has scored a record-breaking 22 goals in his first 15 games for City, and full-back Joao Cancelo at half-time, he replied: "Erling has had a bit of a fever before the game. Joao had a bit of a kick on his foot, that's why we changed it."
Asked whether Mahrez will take the next penalty after his recent miss, Guardiola insisted: "We will see what happens. Of course, it's a problem - we have missed 24 or 25 penalties, most of them in the Champions League and it's too much.
"I admire the courage to take penalties, but this is a problem, and we have to improve. These are the little margins in this competition. Last season, he scored a lot in important moments, here when we got to the semi-final. I admire the courage, but of course, we have to improve."
Guardiola's men visit the King Power stadium on Saturday as they look to beat Brendan Rodgers' Leicester City and leapfrog Arsenal at the top of the Premier League table.