Schalke was one of the continent's busiest clubs Tuesday, with midfielder Jose Manuel Jurado and defender Nicolas Plestan also joining Huntelaar.
Several World Cup stars used their enhanced reputations to switch teams. Ghana forward Asamoah Gyan left Rennes for the Premier League's Sunderland, while Netherlands midfielder Rafael van der Vaart was closing in on a late move to Tottenham from Real Madrid.
But Barcelona, Real Madrid, Inter Milan, Manchester United, Chelsea and Arsenal all resisted the chance to make late additions, reflecting the frugality that has hit the once-frenzied last day of summer trading.
In the Premier League alone, spending was down by $153 million from 2009 summer window. England captain Rio Ferdinand dubbed it the "recession window."
Robinho will be competing for a starting spot alongside newly signed Zlatan Ibrahimovic, Ronaldinho and Alexandre Pato as Milan looks to end Inter Milan's five-year reign as Serie A champions.
"Our goal has to be to win very important titles," Robinho said. "All the Brazilians on the team will give me a big hand inserting myself into the squad. I hope to create a lot of history for this club."
Robinho's arrival enabled Huntelaar to move to Germany on a three-year contract.
Schalke manager Felix Magath, who is revamping the team by releasing veterans, landed Plestan from Lille on a three-year contract and midfielder Jurado from Atletico Madrid on a four-year deal.
The Premier League club Birmingham made three signings, with midfielder Alexander Hleb picked up on a season-long loan from Barcelona, Chile midfielder Jean Beausejour joining on a three-year deal from Mexican side Club America and Spartak Moscow defender Martin Jiranek signing a one-year contract.
Monaco forward Eidur Gudjohnsen is returning to the Premier League after spending part of last season at Tottenham, joining Stoke on a season-long loan. The English club also secured former Liverpool winger Jermaine Pennant for six months from Real Zaragoza.
Liverpool was alone among England's traditional "Big Four" in spending, with defender Paul Konchesky joining the team from manager Roy Hodgson's former club Fulham on a four-year contract.
His arrival was swiftly followed by 21-year-old Argentine left back Emiliano Insua leaving Anfield for Galatasaray on a season-long loan with an option to make the deal permanent.
Joseph Yobo is also moving to Turkey from Merseyside in a similarly structured deal, with Everton releasing the Nigeria captain to Fenerbahce.
The most high-profile arrival in Spain was David Trezeguet's. The former France striker agreed a two-year deal with promoted Hercules in his first foray into La Liga after 10 seasons with Juventus.
In France, Lyon signed Senegal defender Pape Diakhate on a one-year loan contract