Britton has backed his former Swansea team-mate Sigurdsson's class to shine through at Tottenham.
He said: "Obviously, he did brilliantly for us when he came on loan last year and scored a lot of important goals. He played a major part in keeping us up.
"He probably provided us with something that was missing before he came, and that was someone in midfield to chip in with some goals.
"Brendan (Rodgers) brought him in and the impact he had in the four or five months he was here was brilliant. He brought a different dimension to the team.
"When you are at a big club like Tottenham obviously there is competition for places. When you look around that squad, you've got Dembele, who they paid a lot of money for, and some other fantastic players.
"Competition is very fierce there, so it is very difficult for him. I think he needs a run of games, but he is a quality player and his class will come through in the end."