e title since 1990.It is quite the change in fortunes from even a few months ago, when it looked like it would be a straight fight between the two sides for fourth place.
Liverpool are looking for a seventh-straight league win against Sunderland on Wednesday ahead of next Sunday's clash with Spurs, and defender Vertonghen knows exactly what the difference between the sides has been.
"Suarez," he said
"Suarez is the reason for that.
"At the moment he is up there as one of the best strikers in the world
I think he is the difference between the teams.
"(Daniel) Sturridge obviously is doing well and those two are very hard to stop."
Vertonghen played alongside Suarez for several years at Ajax, winning the Dutch Cup together in 2010 and the Eredivisie crown the following year.
The Uruguayan moved to Anfield in 2011 and, after staying at the club following a summer of speculation, has netted 28 goals this term, helping to make Liverpool one of the most dangerous outfits on the continent.
"They are one of the best teams in the league and they show it every week," Vertonghen said.
"It is going to be very hard, especially at Anfield, and I hope we can play as we did last season because we did very well, not the result but the performance."
Vertonghen netted a brace in a late 3-2 defeat at Anfield last term - a fate Southampton suffered at the hands of Spurs on Sunday.
After falling behind to goals from Jay Rodriguez and Adam Lallana, Christian Eriksen strikes either side of half-time drew Spurs level before Gylfi Sigurdsson's stoppage-time strike secured three points.
"It is always good to come back from two goals down but again obviously it was not our best performance, although it is always a good effort," Vertonghen said.
"The manager told us at half-time that we had to improve, put more pressure on them because they were able to play their game, just passing the ball.
"They were passing into midfield and the runners gave us a lot of problems at the back, so we tried to put more pressure on the midfield.
"We have always had good players and Gylfi did very well when he came on
I think we showed good mentality as a team."
That win coupled with Arsenal's 6-0 mauling at Chelsea has seen the gap to the top four close to six points, and Vertonghen is not ruling out a late charge
"We will try as many points as possible and, in the end, we will see what we get," Vertonghen added.
"We will not give up until it is mathematically over
We will try to get as far as possible
With the mentality in the team, there is nothing wrong."
Spurs may eventually have to settle for Europa League qualification, which now looks beyond Southampton.
Mauricio Pochettino's side were usurped in eighth this weekend by Newcastle, who arrive at St Mary's next weekend with Jack Cork looking to make amends for Sunday's disappointment.
"We've got Newcastle next week so if we beat them then everything is back to how it was so that's a massive game for us," the midfielder told Saints Player.
"People look at us in the table and say we haven't got much to play for, but we can now try and get above Newcastle.
"Then we look at the teams above them as we've got Manchester United in the last game of the season, so until then we have plenty to play for."
Source : PA
Source: PA