Rangers boss Stuart McCall says he feels sorry for Gael Bigirimana, but admits he should never have been signed.
Chris Gunter will stay at Reading, after the club took up the option to extend his deal by another year.
Having only narrowly avoided relegation out of the Bundesliga in 2013/14, and having stumbled out of the blocks this term, there are more pressing issues to address at the Imtech Arena.
That means those hoping to see their futures resolved as a matter of urgency will have to be patient.
Hamburg executive Dietmar Beiersdorfer told Hamburger Morgenpost: “I can confirm that we have put everything on hold.
“We are not going to prolong any contracts at this point in time.
“First, we are eager to see what the players are capable of achieving through improved performances.”
Netherlands international Van der Vaart is the most high-profile figure to have entered the final 12 months of his current deal.
He was linked with a move away from Hamburg over the summer and may end up leaving as a free agent in 2015 if no fresh terms are tabled.
Germany internationals Marcell Jansen and Heiko Westermann are also being forced to wait on future talks, along with former Chelsea defender Slobodan Rajkovic, Gojko Kacar, Ivo Ilicevic and Jaroslav Drobny.