Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Darren Bent has revealed an Aston Villa return this summer could be on the cards and discussions have taken place. The former England striker, on loan at Derby County, also said Villa were ‘100 per cent’ correct to sack Paul Lambert. Bent, 31, praised Tim Sherwood, who he knows from Tottenham Hotspur, and opened the door on a shock continuation of his Villa Park career even after his contract expires in June. Darren Bent has scored seven goals on loan in the Championship with promotion-chasing Derby Paul Lambert was sacked by Aston Villa in February after two-and-a-half seasons at the clubDarren Bent currently on loan at Derby County from Aston VillaFormer England striker was frozen out at Villa under Paul LambertBent now says he could be back next season having had 'discussions'Bent worked with manager Tim Sherwood at Tottenham 
 Question:Bent endured a frustrating time at Villa Park while _ was in charge as he was left on the sidelines.

Paul Lambert