Giovanni van Bronckhorst’s men went down 1-0 in Germany from a late strike from Angelino, leaving next week’s tie in the balance.
Rangers frustrated Leipzig for large parts of the game and looked a threat going forward in the second half.
But Sutton reckons the Germans will be a real danger in the second leg to the point Rangers will be required to score two.
"I think to go back to Ibrox with only one goal in it is not the worst result,” he said on BT Sport.
"Rangers fans would liked to have seen their team attack more than they did, but they certainly frustrated Leipzig.
"I thought Leipzig huffed and puffed. They got there in the end with a moment of brilliance.
"But Rangers have work to do because Leipzig can hurt them back at Ibrox.
"I think it will be extremely difficult (qualifying for the final) because I think Leipzig have a goal in them away from home."
Meanwhile, Van Bronckhorst gave a non-committal prognosis over the availability of Aaron Ramsey and Kemar Roofe.
Both were missing from the match in Leipzig due to injury with the hope they would be back for the return leg.
“I cannot comment on that right now,” the Rangers boss said. “Of course, we hope that they are back. It’s a day by day decision we have to make. But we will wait and see who we’ve got available next week.”