Everton's season has been a tale of two halves. Since drawing with Manchester City at the Etihad Stadium, the Toffees have looked a shadow of the team that started the campaign so brightly with four wins from their opening five games.

Ronald Koeman's appointment has restored a positive aura around Goodison Park, while key signings have been made in the hope of reviving the Merseysiders.

For Everton to return to the continental stage, Koeman must make some more key additions, though, and where better than to look at teams likely to suffer relegation this season?

Some players continue to shine despite their parent clubs' lack of progression up the table, and these players should be earmarked as potential winter signings.

Having taken all this into consideration, we here at FootballFanCast believe that these three should be targeted by Koeman.

Gylfi Sigurdsson

Britain Football Soccer - Arsenal v Swansea City - Premier League - Emirates Stadium - 15/10/16 Swansea City's Gylfi Sigurdsson scores their first goal Reuters / Hannah McKay Livepic EDITORIAL USE ONLY. No use with unauthorized audio, video, data, fixture lists, club/league logos or "live" services. Online in-match use limited to 45 images, no video emulation. No use in betting, games or single club/league/player publications. Please contact your account representative for further details.

Despite Swansea's shambolic fall from grace, one player remains head and shoulders above the rest in South Wales, Sigurdsson.

At the moment, Everton have a huge battle on their hands with Ross Barkley continuing to produce performances well below bar, but a move for the Icelandic midfielder would only improve the Toffees chances of rising up the Premier League table.

With the January window looming large, a £20million bid would surely test the resolve of Swansea's new American owners.

Scott Dann

Football Soccer - Crystal Palace v AFC Bournemouth - Barclays Premier League - Selhurst Park - 2/2/16 Scott Dann celebrates scoring the first goal for Crystal Palace Reuters / Eddie Keogh Livepic EDITORIAL USE ONLY. No use with unauthorized audio, video, data, fixture lists, club/league logos or "live" services. Online in-match use limited to 45 images, no video emulation. No use in betting, games or single club/league/player publications. Please contact your account representative for

If not for Scott Dann, Crystal Palace may now be playing their football in the Championship.

The central defensive situation has consistently been a problem for Everton in recent years, and Koeman should be considering a move for the defender with Phil Jagielka ageing.

Palace are statistically the worst team in England, but Dann is far better than many relegation-threatened players. A possible partnership with Ashley Williams would delight the Goodison Park faithful.

Tom Heaton

Britain Football Soccer - Manchester United v Burnley - Premier League - Old Trafford - 29/10/16
Burnley's Tom Heaton 
Action Images via Reuters / Carl Recine
Livepic
EDITORIAL USE ONLY.No use with unauthorized audio, video, data, fixture lists, club/league logos or "live" services. Online in-match use limited to 45 images, no video emulation. No use in betting, games or single club/league/player publications. Please contact your account representative for further details.

Last summer, it was well known that Koeman was keen to find a goalkeeper capable of keeping the No. 1 jersey at Goodison Park for many years.

Maarten Stekelenburg was signed on a free transfer, and despite his solid performances, Koeman's intentions are likely to be to find a shot-stopper over the coming windows.

Tom Heaton has single-handedly kept Burnley in many Premier League games this season and a £10million - £15million is likely to test Sean Dyche's resolve.