Michael Carrick said patience is needed to restore Manchester United to their former glory as he prepares for Sunday's clash against Aston Villa, which could be his final match in charge.
United snapped a nine-game winless run with a thrilling fightback from 2-0 down to beat Roma 3-2 in the Champions League on Tuesday.
The Red Devils have not won in the Premier League since August and sit outside the relegation zone only on goal difference.
Carrick has been handed a stay of execution by the United board, but a two-week international break following the Villa match gives them an opportunity to make a change unless he can prove his team are on the right track.
The former midfielder was part of United's golden age under former manager Alex Ferguson, during which they won multiple major trophies.
The club's fortunes have declined significantly since the Scot retired after the club's last Premier League title-winning season in 2013.
Carrick, though, dismissed the suggestion it is impossible for United to recreate the success that Ferguson built.
"It's not impossible. Anything is possible," he told a pre-match press conference on Friday. "The recent history that we've had and where we want to get to, it's not going to happen in the blink of an eye – it's not going to happen overnight.
"Success does take time, and we don't like having to spend time, but it does take a period of time to build.
"We showed a really quick response and improved a lot last season, and you know it shows what is possible, but again, sustaining it is the key; consistency is the key.
"There's no other way of doing it. There's no shortcuts to it and in the end that's where you get to, but it's definitely possible."
Victory over Roma was marred by the loss of £70 million ($93 million) signing Carlos Baleba for the foreseeable future with a hamstring injury.
Carrick confirmed the Cameroonian will be out for a "number of weeks".