Best Infantry of Renaissance

What is exact timeframe of renaissance warfare ? XVI century ?

If so I would choose the janissaries or spanish infantry..also Zaphorozian Cossacks should be mentioned...

The Janissaries were defeated by German landsknechte at the seige of Vienna in 1529.

Swiss pikemen were good.  They defeated the mounted knights of Charles the Bold of Burgundy in 1477 (Battle of Nancy).

Cossacks were probably the best light cavalry of their time.

The English longbowmen were very good in their day, but were supplanted by the musket.  Actually, I'd say the longbowmen were of the Medieval Period.  Gunpower is a Renaissance innovation.

Spanish infantry, the dreaded tercios, was also good.  Until the modern era, and the innovations of Gustav Adolph of Sweden (died 1632).

And what battle would that be?

Ambiguous term 'best'

The best infantry were the Levellers. They were excellent quality soldiers though far from the finest of the period. But they fought for the finest cause of the era (possible in world history upto that point of time). And they fought freely and on conviction.

Newcastles Whitecoats who fought to the last man at Marston Moor, the Landsnechts & Spanish when the going got tough cut and ran.

Though really the finest troops of the whole renaissance were the New Model Army. The first fully professional army since Roman times and the basis for every modern army in the world today.

That was not always the case--there were plenty of times when landsknechts and Spanish either fought to the last man (Black Legion at Pavia), or cut their way thru ridiculous odds (surviving Spanish infantry units at Ravenna).

Actually, I would consider the Spanish Army of Flanders to be the first.