In 2011 he returned to his previous club and, two years later, left for Napoli, where he won two Coppa Italia tournaments and the 2014 Supercoppa Italiana while appearing in 349 competitive matches (82 goals scored).

[6][7] At the end of the season, Callejón left Real Madrid (with twin brother Juanmi) and signed a four-year contract with RCD Espanyol.

[10] On 15 March 2009, as Espanyol struggled immensely in the league – eventually ranking in tenth position – Callejón scored his first goal for the Catalans in a 3–3 home draw to RCD Mallorca.

[17] Profiting from the fact that his team had already qualified from the UEFA Champions League group stage as leaders, Callejón was handed a rare start by manager José Mourinho on 22 November 2011, and responded by scoring a brace in a 6–2 home rout of NK Dinamo Zagreb.

[34] In the Derby del Sole match against AS Roma on 2 November 2014, Callejón hit the post and had a shot saved off the line before eventually finding the net late on in the 2–0 victory.

[36] On 17 September 2015, Callejón scored twice in Napoli's first game of the UEFA Europa League group stage, a 5–0 home rout of Club Brugge KV.

[37] For the same competition, away to FC Midtjylland on 22 October, he volleyed a long pass from Kalidou Koulibaly to open a 4–1 victory; UEFA dubbed the latter effort an "early contender for goal of the group stage".

[44] Callejón returned to Spain on 25 July 2022 after nine years away, signing a one-year contract with Granada CF with the option of an extension based on sporting performance.

[47] Callejón made his debut for the Spain under-21 team on 25 March 2008 against Kazakhstan in a 2009 UEFA European Under-21 Championship qualifier; he entered the field in the 46th minute after replacing Bojan Krkić, and scored shortly after in a 5–0 win.

[50] A versatile, tenacious and hard-working right-footed player, Callejón was capable of playing anywhere along the front line, and was used as a forward or a winger on either flank, in the centre as an attacking midfielder and as a supporting striker.