He was having a very good 2011 when knee problems ended his 2011 season in late August. Coming back this season, he pitched poorly early on, was sent to Triple-A, came back and pitched mostly poorly again before going on the disabled list with a groin strain early this month.
He's been trying to come back via a Triple-A rehab assignment, but Wednesday night there was another issue. David O'Brien:
Jurrjens was making the second start of his minor league rehabilitation start for Triple-A Gwinnett Wednesday night when he came out after 43 pitches complaining of dizziness. He’s been on the disabled list since Aug. 1 with a strained groin muscle.
O'Brien's article indicates that Jurrjens was treated and released Thursday morning and should be fine, at least from the dehydration. He's thrown eight innings in his two rehab stars so far, allowing four earned runs with a walk and four strikeouts.