The Blues midfielder is still bitter at last season's Champions League final penalty shoot-out defeat in Moscow as well as narrowly losing out on the title to United.
Ballack is currently negotiating a performance-related contract to stay at Stamford Bridge for at least another two years.
He was part of the squads led by Jose Mourinho and Avram Grant which lost out to United in the title race in the past two seasons.
But instead of identifying United as their main rivals as in previous years, he believes Liverpool are now the biggest obstacle.
The German said: "A few weeks ago I was sure United were our strongest opponents but now I think Liverpool are the major threat.
"They have shown in the past few games that they have the character to deal with being top of the league. They have shown they can handle pressure. Liverpool is a team we respect.
"It's not like the past few seasons when they were inconsistent. It's not like it is the middle of October or November - it's the middle of January and they look like they can sustain a challenge for the title."
Ballack, 32, knows plenty about missing out on big prizes in his career after losing two Champions League finals with Bayer Leverkusen and Chelsea.
He also missed Germany's World Cup final defeat in 2002 through suspension but was in the team beaten in last summer's Euro 2008 final.
But he has warned any of his team-mates who have not mentally overcome last year's final defeat that they will end up trophyless again unless they move on.
Ballack, who has yet to score for Chelsea this season, said: "Are any of us suffering hangovers? I can't speak for everyone personally but of course it was a huge disappointment.
"As a sportsman you have to deal with the situation. It has happened and you have to move on. Sometimes you win, sometimes you lose. If you look back all the time and maybe cry over this, then you'll win nothing because you will lose all your strength.
"It's normal that if you live in the past and think too much about it you'll win nothing."
This article has 6 comments
Ballack has a problem! SOMEONE PLS CALL 911. He should focus on his dwindling career. Infact he was advised by FRANZ not to sign for chelsea but he did not listen...He will dream of becoming a champion but he will never feel being a champion. MAN UTD GLORY GLORY GLORY GLORY
By Conrad. Posted January 12 2009 at 9:02 AM.
Its not surprising that frustration is already hit Ballack.Coming to Oldtraford will not be an easy thing for Chelsea.Remember they almost lost at the Bridge.Ballack is a seasoned looser and by him being shipped in the squard,it already bad luck for Chelsea.Manutd for life.
By Toskin Ebulu. Posted January 11 2009 at 12:59 PM.
How many goals has he scored????????
By Bernie. Posted January 11 2009 at 11:06 AM.
if ronaldo had not been lucky and had not steped out of his wrecked car unhurt , along with another first team player we would be talking about more important issues . and fergusion would have had more on his mind than talking about other teams and their pressures , but i think his end of season mind games has backfired on him this time this liverpool manager has exposed rent a gob,, mr ferguson would be better useing his time explaining why ronaldo almost endedutd s title race. but then again last year proved one thing he s afraid of ronaldo
By hg. Posted January 11 2009 at 10:51 AM.
aahh, ballack is very funny he also wishes he would have been man u player but only money in this morden world is the problem, the man u room for trophies is full and now we want to expand it for premear,carling,fa i am not sure about eufa champ.
man u forever.
By james deo-tanzania.. Posted January 11 2009 at 9:55 AM.
this man is a joke every time we play them he comes out with daft comments like this and as for chelsea regaining there crown isnt it manchester united that are world european and english champions that makes the trophy ours to regain and i am sure we will. ballack still wishes he would of come to utd but like most of the chelsea players he put money before glory. champions champions champions.
By steve gill. Posted January 11 2009 at 8:05 AM.