Sigurdsson - No regrets over Liverpool snub
Unbeaten in 12 league games, including last weekend's victory over Arsenal in the north London derby, Andre Villas-Boas's team are up to third in the Premier League, five points behind second-placed Manchester City, while seventh-placed Liverpool are hoping to make a late surge into the top four.
Tottenham, though, have also been lifted by their impressive form in Europe and they travel to Merseyside on Sunday after a memorable 3-0 Europa League victory over Inter Milan in midweek.
That run has only strengthened Iceland midfielder Sigurdsson's view he made the right choice when he returned to England following an �8 million move from Hoffenheim.
The former Swansea man had been expected to be reunited with Brendan Rodgers, his old manager at the Liberty Stadium and now in charge at Liverpool.
But Sigurdsson said: "It was hard to turn them down because I knew Brendan. It wasn't about the history Liverpool have. Tottenham came in for me and you can see how well they've been doing over the last few years.
"They finished fourth last year and were unlucky not to get in the Champions League, and they did well in the two years before that. This is a great club with fantastic players and I'm pleased I made the choice I did.
"Hopefully it's the right decision. You never know how things might be, we could have been seventh in the table and they could have been third, but there are many good players here and hopefully we can be in the Champions League next season.
"It will be good to play against Brendan's team but it's about getting three points."
Gareth Bale again shone in the victory over Inter and, having been ruled out of the return in Italy after collecting a yellow card in the first leg, will definitely start on Sunday.
Rodgers, meanwhile, believes his Liverpool side are finally fulfilling their potential as they enter the final stretch of the season.
Since Rodgers' arrival from Swansea last season, the Reds have struggled to reach the consistency required to mount a sustained challenge for a place in the top four and they remain 10 points behind fourth-placed Chelsea ahead of Sunday's match.
Following the convincing 5-0 and 4-0 wins over Swansea and Wigan, the Reds team will be looking for a third straight Premier League victory for the first time this season.
Rodgers thinks his players are starting to click and he said: "We've played a lot of really good games this season and maybe weren't as cohesively good then as we are now.
"We've played 28 games - after 14 games we were 12th in the league. If you take the points total from the following 14, we'd be third.
"It's going how I thought it would go, which would be improvement as the players became accustomed to how we work.
"Because of the great attitude of the players - they've really embraced the work - they're getting the rewards. At this moment in time, the level is very high and we want to continue with that."
Reds striker Daniel Sturridge is set to return after a knee injury, while defender Martin Skrtel is also available again after illness.