Sunderland completed some excellent business during the January transfer window.
N’Doye and Kirchhoff were two of the players who Sunderland recruited in the January transfer window, alongside Wahbi Khazri and Lamine Kone.
The quartet have all played important roles in Sunderland’s survival fight, but Allardyce admits his intention was always to put Khazri and Kone straight into his team.
The 61-year-old has been taken aback by how quickly Kirchhoff and N’Doye have adapted, though, as they had not played much football prior to their move to the Stadium of Light.
“Kirchhoff had hardly played for eight to nine months, and Dame was bombed out in Turkey for some reason,” Allardyce said.
“Kone had been playing very, very well at Lorient and Wahbi had been doing the same at Bordeaux, so the likelihood was that those two would be alright straightaway.
“But the other two hadn’t had many games, so for them to all catch up and be as good as they have been, is one of the main reasons why we’ve been as good as we have.”
Kirchhoff has played a key role for Sunderland since arriving, with Allardyce stationing him as a defensive midfielder.
The rangy German has thrived in a protective role in front of the defence, and his performances have been of a consistently high standard.
N’Doye’s appearances have been more limited, but he has still made a decent impact off the bench and has enhanced the Black Cats’ attacking options.
Sunderland’s January signings have helped the side move out of the relegation zone, and their task will now be to ensure that they don’t slip back into the bottom three again.