View the photos from the Blues' league loss at Fratton Park
A disappointing January was brought to a close with a 1-0 home defeat to Shrewsbury.
James Bolton was left in space to convert a corner for the high-flying visitors midway through the first half.
Pompey had a number of chances to get something from the game, with Brett Pitman hitting the woodwork and keeper Caig MacGillivray making some fine saves.
But there were also moments of controversy, with the Blues having strong penalty appeals turned down, while Adam May was sent off late on.