Erik ten Hag never does things the easy way. The Manchester United manager had complimented Marcus Rashford’s improved attitude but left him on the bench and then watched his replacement, Alejandro Garnacho, fail to find a way past the outstanding Dean Henderson, who was inspired against his former club.

By the time Rashford made it on to the pitch in the second half, a strangely off-colour Crystal Palace had finally woken up and United needed a brilliant double save from André Onana to avoid a second successive defeat in south London against Oliver Glasner’s side. Lisandro Martínez was fortunate to escape a red card for a reckless challenge on Daichi Kamada but at least this was a much-improved display from the 4-0 debacle here in May that was the low point of last season under Ten Hag, with United’s defence standing firm in the face of late pressure.

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Having praised Rashford after three goals in his last two appearances, more than a few eyebrows were raised when Ten Hag preferred Garnacho in United’s only change from the win over Southampton last weekend. Even more bizarre was the manager’s insistence that the England forward’s absence was “not a difficult decision because we have to rotate” as they also welcomed back Mason Mount and Rasmus Højlund to a strong bench containing nine internationals. It was quite a contrast to United’s last visit to these parts 138 days ago when their bench had included two goalkeepers and four players who had never made a senior appearance.

Much has changed for Glasner since the heady days of that famous victory which was inspired by Michael Olise, with the France forward having starred for his new team, Bayern Munich, in a 5-0 win over Werder Bremen earlier on Saturday. Palace desperately missed his creativity as United controlled the first half and should have gone ahead. But Glasner’s changes at the break had the desired effect as Eberechi Eze wasted a golden chance to snatch all three points while substitute Ismaïla Sarr was somehow denied by Onana.

United had seemed intent on picking up where they left off in the 7-0 thrashing of Barnsley in midweek and would have been ahead in the opening 15 minutes if not for Henderson. The Palace goalkeeper, who spent eight years at Old Trafford but made fewer than 30 appearances, first denied Garnacho after he had been played in by Joshua Zirkzee before keeping out Matthijs de Ligt’s header and a near-post effort from Martínez in the space of 60 seconds as Palace’s defence was caught napping.

The hosts struggled to find any rhythm as Kobbie Mainoo and Christian Eriksen had the edge in midfield, with Glasner letting his frustrations be known on the touchline. Somehow they escaped when Maxence Lacroix was culpable of ball-watching and allowed Diogo Dalot to feed Garnacho. His shot cannoned off the crossbar and fell to Bruno Fernandes but the United captain’s volley into the ground bounced up and struck virtually the same spot. Zirkzee was then unfortunate to see the smallest of touches divert a cross from Fernandes away from Garnacho at the back post with the goal gaping. Palace finally mustered their first effort on target two minutes before the break but Eze could only fire straight at Onana.

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Glasner opted to replace both Jean-Philippe Mateta and the struggling Adam Wharton, who has been taking painkillers to cope with a groin injury, for the second half and Palace immediately looked more threatening. De Ligt was required to slide in to stop Eze after a brilliant pirouette was followed by a smart one-two with Eddie Nketiah.

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A flowing move for United started by Mainoo ended with Fernandes shooting just wide. The stage seemed set for Rashford when he was introduced for Zirkzee just after the hour but Garnacho was next to test Henderson after he was set up by Dalot. Only Martínez will know what possessed him when he jumped two-footed into a challenge on Kamada on the edge of Palace’s box but referee Chris Kavanagh only showed a yellow card. United then had their goalkeeper to thank when Onana recovered brilliantly after saving Nketiah’s drive to stop Sarr’s follow-up from point-blank range when it seemed easier for the substitute to score.

The Senegal forward could hardly believe his luck but it was his awareness that set up Eze minutes later, only for his shot to flash past Onana’s post. Højlund was given the last 15 minutes on his return from a hamstring injury, although neither side looked capable of finding the breakthrough as Palace’s search for a first win of the new campaign continues.