The forward failed to impress in United's 1-0 win at Aston Villa on Friday as Louis van Gaal's men secured successive opening wins.
Depay should have scored in the second half but shot wide with only Brad Guzan to beat as United relied on Adnan Januzaj's winner.
But Blind, who partnered Chris Smalling in defence at Villa Park, reckons his Dutch compatriot Depay will come good following his summer move from PSV Eindhoven.
"I think it's a matter of time for Memphis
You've seen how much quality he has and how strong he is," he told MUTV.
"We can see some nice things from him.
"He's just got to keep going, he tries very hard and the goals will come for sure."
United followed up last week's 1-0 win over Tottenham with a comfortable victory at Villa Park which extended their unbeaten Barclays Premier League record at the stadium to 20 years.
Van Gaal's side were rarely troubled and Blind insisted their team ethos is paying off.
He said: "It was something we talked about, starting afresh for the away games, but it's a good start
Last year, we gave some things away in the games, but now you've seen how strong we are at the end - we kept a clean sheet and fought for everything.
"I think again it was a real team performance, especially off the ball
We created some chances and we could have scored more, but we didn't give anything away and won 1-0
Three points are the most important thing."
Villa never tested United goalkeeper Sergio Romero, who again replaced David de Gea, even when new striker Rudy Gestede made his home debut as a substitute.
Boss Tim Sherwood is easing Gestede, a summer buy from Blackburn, in after an interrupted pre-season but he warned his side not to forget their strengths.
"When he came on, we got a bit obsessed about lumping the ball up to him," he said.
"They obviously took their backline back and there was a lot of space in front of them and that's when we need to recognise that we can pass the ball."
Winger Scott Sinclair added to AVTV: "I think where we kept the ball we created a little bit but there were other times where we had our backs against the wall and had to defend
It's disappointing losing and not getting any points."
Source : PA
Source: PA