Keinan Davis struck midway through the second-half to cancel out Pietro Pellegri's opener for Empoli.
Runjaic later said: "I'm not happy with the performance overall, but with the result, yes. The team has grown with the changes, we need to work.
"We have more options, we've been thinking about it for several weeks and it's a possibility. This is an opportunity to have more power, when necessary. The team has managed to create more chances and has brought benefits.
"They play a lot of man-to-man, one-on-one. We knew it, we were a bit too passive without managing to pass the ball well. They play aggressively, we expected it, it's nothing new. In the first half, we had possession but we didn't exploit it, in the second half we improved and took control of the game."