Inter Milan signed Zdravko Kuzmanovic, Ezequiel Schelotto and Mateo Kovacic during the January transfer window to help fill midfield gaps left by Philippe Coutinho and Wesley Sneijder.
Serbia cruised to a comfortable 2-0 win over Armenia after first-half goals from Zdravko Kuzmanovic and Branislav Ivanovic all but settled the contest before the break.
Borussia Dortmund clinched the Bundesliga title with two games to spare, Bayern Munich thrashed Schalke 4-1 to move back into third, while Stuttgart eased their relegation concerns.
Hannover were unable to take advantage of playing ahead of nearest rivals Bayern Munich, as a 0-0 draw with Hamburg leaves them just two points ahead in third, while a 3-1 win for Stuttgart sees them gunning for safety.
Three second-half goals set Stuttgart on their way to a 3-1 victory at Cologne, which moved them four points clear of the relegation zone and ended the hosts' eight-match winning run at home.
Stefan Reinartz and Stefan Kiessling scored goals in the final ten minutes to give second-placed Bayer Leverkusen a 4-2 victory over struggling Stuttgart and reduce the gap to Borussia Dortmund to ten points.