Philippe Clement was pleased with the improved second-half performance of his Rangers side but suggested the bar was low during the 0-0 draw with Hearts.
Rangers started the encounter poorly, but Clement took encouragement from the improved display in the second 45 minutes, with Cyriel Dessers going closest as his header crashed against both crossbar and post.
Hearts had the better of the Scottish Premiership opener, having 18 shots to Rangers' nine, and 0.78 of the hosts' 1.28 expected goals (xG) was mustered in the first half.
Clement said: "We showed the right images in half-time, we talked, we discussed, to do the right things – and then you see that we play better football and we create more and we have much more control of the game.
"We need to continue that way – like we played in the second half."
Despite the uplift in performance, Clement underlined how poorly he felt his players performed in the first half, most notably when they were without the ball.
He said: "In the first half, I could have changed, maybe eight. They need to understand that it's not only with the ball – you need first to win the duels and we lacked that in the first half.”
"In the second half we were much braver with the ball, with the right positioning also."
Clement's observations were backed up by the match statistics, with Rangers winning just 38.5% of their duels in the first half.
Rangers' manager was pleased enough with the performances of his debutants Connor Barron and Vaclav Cerny but hinted at more reinforcements before the end of the summer transfer window.
He added: "Connor played a good game, but not at the level that he played in the pre-season, but also it's his first competitive game. He will be a big asset for the future.
"You saw Vaclav's qualities to be calm on the ball and to make the right decisions. He's an experienced player with a lot of quality.
"We need to get a few more of those types in to help our young players to grow."
It is a quick turnaround for Rangers before their next match, as they face Dynamo Kyiv in a crucial first-leg Champions League play-off on Tuesday.