Notts County head coach Martin Paterson warned he will not allow his team to rest on its laurels following a 1-0 victory over Gillingham.
Despite being without their most prolific marksman Alassana Jatta and the influential Jodi Jones, County reiterated their automatic promotion ambitions by recording a fifth straight win which lifted them to second in the League Two table.
The hosts seized the initiative in the 27th minute thanks to Robertson’s third goal of the season.
But Paterson’s team were indebted to James Belshaw for making fine saves to deny Gillingham substitute Sam Vokes and Omar Beckles during the closing stages.
Paterson said: “There is still room for improvement and that has to be the mentality.
“Listen, I’m not going to be hard on them because I’m so proud of the group. They are aligned and they fight for every single ball and they fight for the badge.
“But the mentality has to be, ‘How can we get better?’ I think we can.
“It’s simple. Don’t get carried away and just look to the next game. That’s all that matters, nothing else.
“They can enjoy a good result tonight but tomorrow, when they come back in, they have to try and be ready to improve.
“As a staff, we show them bits and pieces and things we believe, things we know, they can do better. They also have to show that attitude, which they have.”
Robertson slotted through Seb Palmer-Houlden’s legs and inside Glenn Morris’ near post after combining with Ollie Norburn to open the scoring.
County went close to extending their advantage when the excellent Nick Tsaroulla and Maz Kouhyar both shot inches wide.
But Gillingham improved during the closing stages and pushed hard for an equaliser that manager Gareth Ainsworth insisted their performance warranted.
“How we didn’t score, how we didn’t get anything out of the game, it’s beyond me,” he said. “But we made a mistake in the first half and got punished for it.
“They had a couple of chances in the first half but then, in the second, I thought we were the dominant side. It was incredible that we didn’t get one right at the end.
“When the whistle blew, all of the County lads went rushing over to their keeper and were hugging him because he knew they’d won them the game and this is a tough place.
“I just told the boys at the end, ‘Be proud of that. But cut out the silly mistakes’. If we do that, then we go home with a point and knowing that we should have won the game.
“It’s all about the bigger project, though, and we are much improved from where we were a year ago.”