The Spaniard took the reigns in the summer to replace Bruce, who had departed to join Sunderland. Bruce was thwarted by his former side when the Black Cats travelled to Wigan earlier in the season but gets the chance to even the score at the Stadium of Light on Saturday. And Martinez claims that Bruce's actions in the transfer market left the squad in need of a major upgrade. "I knew when I came here there were big changes needed because the club had lost many players - Heskey, Zaki, Palacios, Cattermole," he told the The Sun. "Very important players had gone so I was aware we had to make the signings to improve the size and strength of the squad. "In some departments we very thin but hopefully I've addressed that now. "When you get a new group, you're looking at a new way to play and a new philosophy." After bringing in a raft of new faces before the start of the season, Martinez was once again quick to open the chequebook in January. Hot prospect Victor Moses joined from Crystal Palace for £2.5million but Martinez thinks that fellow new boys Marcelo Moreno and Gary Caldwell will also be valuable additions to the squad. He added: "Victor has a lot of options in the UK but also abroad. For him to choose Wigan is a great boost. "In Marcelo Moreno we have another diamond and Gary Caldwell has brought leadership qualities."
