The 23-year-old Argentinian scored twice - the second a stunning right-foot blast from 30 yards - and created another for David Silva during a 30-minute cameo as a sub against Swansea.
Now he is in line to start the match tomorrow.
Asked how Bolton can stop him, Steinsson said: "We'll defend as a team, though we know we'll have to be at our highest level.
"We know if you give him time, he'll punish you.
"You don't have to analyse him. He did it all in the 30 minutes against Swansea.
"He is good on the ball, he is good left and right, goes in behind you or drops off.
"It does not matter where you give him space, he is going to be dangerous wherever he goes.
"Aguero has that little bit extra that everyone loves to watch."