Keeper Victor Valdes, defender George Friend and midfielder Marten de Roon have all returned after injury, and with the additions of Adama Traore and Calum Chambers last week, the Spaniard has a wealth of options for Saturday’s clash.
“I like that. I prefer to have that than just having 10 or 12 players,” said the Boro boss.
“The best thing is they have all played really well and those who have played so far have done really well.”
Karanka brought in 11 new signings to boost his first-team squad during the transfer window.
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He is delighted with the business Boro have done, and he revealed that it was all down to the early planning just days after winning promotion.
Karanka said: “I was really pleased but not just at the end.
“I said always my experience in first few years was crucial to try and do everything as quickly as possible.
“We had our first meeting days after winning promotion so it means we went to Spain with new players.”
Boro have made an unbeaten start to the season and few would forgive Karanka for feeling aggrieved at the timing of the recent international break.
The 42-year-old coach, however, believes it arrived at the perfect time.
“I think it was at the right moment because we knew this season we are lucky because we have a lot of players in international teams which shows we’re doing good things here.
“We have started really well this season but we shouldn’t get carried away.”
Fabio, who joined from Cardiff last month, is expected to be out for around six weeks after injuring himself on his debut and long term absentees James Husband and Grant Leadbitter are unavailable for the clash with the Eagles.
Cristhian Stuani and Gaston Ramirez will be assessed on Friday by Karanka after travelling back from international duty in South America with Uruguay.