The 25-year-old has returned to the Liberty Stadium from Villarreal after a successful Premier League campaign last season, scoring five goals in 33 appearances.
De Guzman linked up with the squad for their pre-season tour of the Netherlands on Monday and will hope to feature against Den Haag on Saturday.
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|16/1||Swansea are 16/1 with William Hill to finish in the top six
"Last season went well and I was very happy. But I’m looking forward to coming back and having another good season with Swansea.
"I only started training a couple of days ago so its case of getting fit and on a par with the other lads and get some minutes under my belt against Den Haag."
Netherlands international De Guzman is part of an overhaul by boss Michael Laudrup this close-season, and joins fellow new signings Jose Canas, Alejandro Pozuelo, Jordi Amat and Jonjo Shelvey at the club.
All form part of the touring pre-season party, with Swansea having beaten Haaglandia 10-0 on Wednesday.