Both were at Wigan Athletic last season under current Everton boss Roberto Martinez, with Alacaraz moving on a free and Robles joining for an undisclosed fee.

Paraguayan Alcaraz, who spent the last three seasons at Wigan, joins on a two-year contract after his deal with the FA Cup winners expired.

Alcaraz, who joined from Club Brugge in 2010, became a mainstay in the Wigan defence under Martinez, who took over at Goodison Park from David Moyes in June.

However, his 2012-13 campaign was blighted by injury, with his absence credited as a key factor in Wigan's relegation to the Championship.

The 30-year-old, who has 24 caps for his country, made 14 appearances in all competitions last term.

Robles joins on a five-year deal from Atletico Madrid having played eight times for Wigan last season.

According to Everton, Robles will challenge regular number one Tim Howard for a starting spot in Martinez's line-up.