Ole Gunnar Solskjaer says Manchester United must be "smart and clever" in what will be a "strange" summer transfer window.
United finished third in the Premier League to secure Champions League qualification, but semi-final exits in the Carabao Cup, FA Cup and Europa League show there is work to be done.
The Red Devils will need key signings to try and bridge the gap to champions League and rivals Manchester City, who have already been busy in the transfer market.
Jadon Sancho is Solskjaer's priority target, though Dortmund's £108million asking price remains a sticking point - and the financial impact of the coronavirus pandemic has hit United's transfer budget.
The window remains open until October 5, but time is of the essence given that the new season starts on August 12.
Solskjaer's three signings this season - Harry Maguire and Aaron Wan-Bissaka last summer, and Bruno Fernandes in January - were all successes, and Solskjaer is now looking for the Glazers and Ed Woodward to back him again to take the next step.
"It’s going to be a strange summer," Solskjaer said. "We’ve only got a couple of weeks away from each other before we get going again. That’s going to be a mental challenge.
"Of course, we’re going to keep pushing and keep demanding more of the players we have but still we’re looking to improve. It’s a strange one.
"The League starts very quickly but the market is open for so long. We’ve got to be smart and clever.”
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Regarding signings, Solskjaer added: "Well, I cannot say when or if transfers are going to be done. We’ll need to look at it and we’ll have to sit down.
"It’s a quick turnaround and we’ve got to be 100 per cent sure when we make those deals."