Hagar said having a top-class player such as Northland's Charlotte Harrison return after a self-initiated break from international hockey was a welcome addition to his side.
He added that Harrison was under some pressure to perform with so many fresh faces pushing for her spot.
"[It was] good to have her back" Hagar said. "She knew she had to come back and play well to be considered for future selection so it's pleasing to have her back and see her playing pretty well.
"As you would have seen our young girls are putting a bit of pressure on those spots ... we're obviously starting to get a bit of depth in our squad now.
"For the young ones you give them an opportunity and some of them will take, so that's what we've tried to do is give them a go."
Harrison said being back in the team has enjoyable, especially to play and win three in a row in front of her home crowd.
"We turned it on for the home crowd so happy with how we went [yesterday]," Harrison said. "I was a little rusty to start with in the first game [of the tournament], but we learnt from our mistakes and came back firing.
"Today [Sunday] our starting line-up was pretty similar to the London one so it was pretty good just to slip in that way, but I mean the new girls have come along since they first started."
Next week the Black Sticks travel to Hamilton and Tauranga to repeat the tournament against the same teams.
The New Zealand team will make five changes ahead of it to give more young players a chance to impress.