Steven Gerrard was less than impressed with his team's approach to the second 45 minutes in their 3-1 win against Hamilton.
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Rangers survived three close shaves as Hamilton pushed for an equaliser before Ryan Kent sealed the points with his second goal of the game after Lewis Smith cancelled out Ryan Jack's opener.
Rangers now turn their attention to Thursday's Europa League clash with Feyenoord, with a win at De Kuip meaning the Light Blues follow Celtic into the last 32.
But Gerrard says his team will need to sharpen up.
"It's another positive result and three points away from home against a team who were very competitive and gave their manager everything they had," he said. "So you have to give Hamilton a lot of respect and credit.
"Our performance was very mixed. At times, we looked like we had a lot of quality and created lots of chances. But, at times, we looked a bit vulnerable as well.
"We haven't been ruthless or defended well enough. We have to be better in the final third and kill teams off.
"We'll need to find a better performance than today. Today was good enough because we win the game and the points we've got are important.
"But we're going into a game away to Feyenoord we'll need to find a better performance."
Defeat sees Hamilton drop to second bottom but manager Brian Rice insists his men are not going down lightly.
He said: "We are going to be in a dogfight. Let's not make any mistakes about that. There are going to be five or six teams in a dogfight and we are going to be one of them.
"But I'll tell you one thing: we are always up for a fight. You saw a team out there today that never gave up.
"They play for one another, for me and for the club. There will be good days and there will be bad days."