Former Rangers manager Ally McCoist is concerned that Sunday's victory over Celtic might lead to complacency about the task ahead at Ibrox.
Rangers were well worth a 2-0 win as they sealed a second derby success of the season.
The victory, Rangers' sixth in a row, cut the deficit at the top of the Ladbrokes Premiership to six points.
But Celtic had wrapped up their eighth consecutive title the previous weekend and are going for a triple treble in the William Hill Scottish Cup final against Hearts on May 25.
And McCoist has warned that Steven Gerrard still has a big job to close the gap completely.
He said on talkSPORT: "I was on the phone to Walter (Smith) and my big concern is this: Rangers think they're a lot nearer Celtic than they potentially are and maybe just take their eye off the ball.
"It's a massive summer for both Rangers and Celtic in terms of their recruitment.
"Steven will have to get support and maybe get two or three in that will go straight in the team, but equally there will be big changes at Celtic as well."
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