FABIO CARDOSO admits Rangers must improve if they are to overcome Partick Thistle at the second time of asking on Tuesday night.

The Light Blues dropped another two Premiership points on Friday as they had to come from behind to earn a draw at the Energy Check at Firhill Stadium.

Alfredo Morelos gave Pedro Caixinha’s side a dream start against the Jags but Rangers couldn’t capitalise on their early advantage.

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Blair Spittal curled home a free-kick to pull Thistle level before Chris Erskine put the hosts on course for a famous derby win.

A red card for Erskine gave the Gers hope and Graham Dorrans salvaged a share of the spoils with a terrific strike 13 minutes from time.

But it was a frustrating night for boss Caixinha and his players as they failed to make the most of their chance to go top of the Premiership standings.

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Rangers will now return to Firhill for a Betfred Cup quarter-final clash and defender Cardoso knows they must raise their performance levels at both ends of the park.

“It was a hard game and we can’t commit mistakes like that,” he told RangersTV. “We scored two goals and with two goals scored we can’t lose the game.

“We committed a lot of defensive mistakes and we can’t. We have to improve and do better on Tuesday.

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“We have to play fast to improve and win because we deserve to win. We are more than we showed [on Friday].

“It [the start to the second half] is something we have to improve. We have to control the game because teams start very strong against us.

“We have to start stronger and we have to improve in the next games.

“After we conceded the second goal, we tried the whole game to score. We scored one but we needed two.”