Watford have snapped up midfielder Iriney from Granada and defender Joel Ekstrand from Udinese.
Sky Sports sources understand that Watford are close to signing eight players on permanent deals.
Watford boss Gianfranco Zola praised his team's resolve as they held on for a 2-1 victory over Derby.
Udinese have completed the signing of Joel Ekstrand from Helsingborgs on a four-and-a-half-year deal.
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