Where this thoughtful exhibition struggles is in overcoming the problem that Mantegna's single most important work is immovable - the frescoes of the Camera degli Sposi painted between 1465 and 1474 for the Gonz-aga's ducal palace in Mantua. Mantegna had become their court painter in 1460 and the extant works of his maturity were all painted for the Dukes of Mantua. Several notable examples are here; in particular, the verdant and hieratic Madonna della Vittoria, commissioned to commemorate a narrow victory over the French in 1495, and two of the bizarre mythologies he painted for Isabella d'Este, Parnassus, 1496-7, and Minerva Chasing Vice from the Garden of Virtue, 1500-2.

The presence of these pictures papers over some of the gaps in the narrative. Indeed, as an example of how to make the most of limited resources and give a real sense of the development and influence of this most innovative and idiosyncratic of artists this exhibition could hardly be bettered.

The Louvre also contains one part of Paris's current Picasso-fest - an idea with a very different ethos. Spread over three sites, this ambitious composite show puts the Spaniard's pictures alongside the works of earlier painters who inspired him. At the Louvre, several of his versions of Delacroix's Les Femmes d'Algers are juxtaposed with the real thing, at the Musée d'Orsay it is Manet's Déjeuner sur l'herbe, and at the Grand Palais, in Picasso and the Masters, he squares up to an enormous selection of greats from Raphael, Titian and Velázquez to El Greco, Poussin and Goya.

The exhibition was carefully designed to be the biggest blockbuster in living memory: take the most crowd-pulling of the moderns and then lard the mix with a greatest hits medley by many of art's most celebrated names. The whole thing cost some £3.3 million to stage, the 200 paintings involved are worth an estimated £1.67 billion and 10,000 visitors a day have turned the Grand Palais into a mainline station at rush hour. All this to prove that Picasso was the heir and equal to the greatest painters in history and that he cannibalised them to make a new type of art - the painting of painting.