Bale has illuminated the division so far this season, scoring 21 goals in 36 appearances in all competitions and helping Andre Villas-Boas's side climb to fourth, with a strong chance of qualifying for the Champions League.
In contrast, many of City's big names have struggled to replicate the form that saw the club crowned champions last season, and Zabaleta believes they are now playing catch-up to Bale.
He told La Gazzetta dello Sport: "The best Premier League player? Gareth Bale, a force of nature."
One man who would have liked to have laid claim to the status of league's best player during his time in England was former City star Mario Balotelli.
The mercurial Italian left Eastlands for AC Milan in a £19million deal during the January transfer window, ending a turbulent two-and-a-half-year stint in Manchester.
The 22-year-old has gone on to make an instant impact at the San Siro, scoring seven goals in six appearances and injecting fresh impetus into the Rossoneri's season.
Zabaleta witnessed all of the highs and lows of Balotelli's City career and believes it was the right decision for him to return home.
The Argentine full-back said: "I think Balotelli's departure was inevitable. It had become a difficult situation.
"Mario is a great player, who must learn to better manage his life off the field. He should be more disciplined and quiet. Returning to Italy and staying near to his family is helping him."
City sit 15 points adrift of arch rivals Manchester United in the Premier League and appear certain to relinquish the title they won so dramatically last May.
Zabaleta is disappointed with the way in which the season has developed, but insisted he has not lost any faith in manager Roberto Mancini.
"My relationship with Mancini is great," he added. "You can talk with him not only about football, but also life problems.
"We [City] must grow as a group and in mentality. United have built a winning culture over the last 20 years, while City's project is at the beginning."