Within four days of being fired by Sheffield Wednesday, Carlos Carvalhal has achieved what eluded him at the second-tier club: Promotion to the English Premier League.

Keeping the job at Swansea beyond the end of this season is likely to depend on whether the south Wales club wins the battle against relegation for a second successive year.

The 52-year-old Carvalhal is Swansea's fifth manager in around two years — a reflection of the struggles on the pitch and disjointed thinking in the boardroom at the 2013 League Cup winner which was previously lauded as a model club.

The journeyman Portuguese coach inherits a team from Paul Clement that is bottom of the standings and five points from safety with 18 games remaining.

"In this moment, maybe if you ask 100 people who follow football," Carvalhal said on Thursday, "they will say Swansea are going to get relegated."

The form points to that: One win in 12 games, with the latest loss a 5-0 collapse at Liverpool on Tuesday, and a league-low 11 goals in 20 games.

"A lot of people would say we need a miracle to stay in the Premier League," Carvalhal said. "But I don't agree, because miracles are not something from our world. Our job is to win."

The appointment is another gamble by restless American owners Stephen Kaplan and Jason Levien. Last season's paid off, in the short term. Clement, who was hired in January after Bob Bradley's ill-fated 85-day tenure, kept Swansea in world football's richest league but the drop in form led to his dismissal before reaching his first anniversary.

Carvalhal has no previous experience coaching in the English top-flight, or any of the continent's major leagues. Although Carvalhal led Sheffield Wednesday into the playoffs for promotion to the Premier League in each of his full seasons in charge, he fell short on both occasions. And after a seven-game winless run led to Wednesday fans calling for his dismissal at the weekend, the mid-table northern English club did just that on Sunday.

Far from arriving in Swansea with a diminished status, Carvalhal insisted he was a manager in demand.

"In a very short time I received a lot of offers from different parts of world," he said.

Carvalhal has been given a contract for only the second half of the season at Swansea, but there is an option to extend it.

"We felt we needed to get the managerial situation resolved as soon as possible and while the timing is not always perfect, we can look forward to the second half of the campaign with renewed optimism," Swansea chairman Huw Jenkins said.

One of the symbols of Swansea's struggles this season has been Renato Sanches. The winger left Bayern Munich on loan in an unexpected move in the summer transfer window, but he has failed to demonstrate in the Premier League why he was once being talked about as Portugal's natural heir to Cristiano Ronaldo barely a year ago.

One of Carvalhal's missions is to revive the fortunes of his 20-year-old compatriot.

"He needs confidence," Carvalhal said. "It is easy to forget because he has played for Benfica and the Portuguese national team that he is still only a kid. He needs a role in the team. With time he and the other players will understand the different roles they have in the team.

"He will be involved in the dynamic and when he understands what we want, he will be a completely different player."

That could depend on Carvalhal's ability to bring the free-flowing football back to Swansea, but for now gritty results are required to amass points.

"He has built up a lot of experience over the years which will ensure the team is structured and organized," Jenkins said. "He is driven and ambitious and while he has a big challenge ahead of him, I know he will tackle it without fear."

It is not the first time hiring Carvalhal has seemed a gamble. He had been out of work for three years when he was handed his first job in England in 2015 by Sheffield Wednesday.

Before then, he had mostly drifted around jobs in Portuguese leagues but there were also stints in Greece and Turkey.

Among the career highlights was leading third-tier Portuguese club Leixoes into the now-defunct UEFA Cup in 2002 after reaching the final of the Portuguese Cup. He later steered Vitoria Setubal into the Portuguese top-flight, returned to the UEFA Cup via a sixth-place finish and won the Portuguese League Cup.

His highest profile jobs came between 2009 and 2012 when he coached Sporting Lisbon and Besiktas in Turkey.