Detailed Instructions: In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.
Problem:Passage: Impressing at non-league Halifax Town, he turned professional with Doncaster Rovers in 2005. Used sparingly in 200506, he was loaned out to Oxford United in March 2006, though did not make it onto the pitch. In 200607 he was loaned out to Darlington and Stafford Rangers, before he spent the 200708 campaign on loan at Halifax Town. In April 2008 he signed with Port Vale, and became a first team regular in 200809. He remained a key first team figure in 200910 and 201011, and was voted the club's Player of the Year in 2010. He continued to impress for the "Valiants", and earned a move up a division to Leyton Orient in May 2012. He returned to Port Vale on loan in March 2013, and helped the club to secure promotion out of League Two in 201213, before re-joining on a permanent basis in the summer. He signed with Shrewsbury Town in August 2014, before moving on to Carlisle United in January 2015. Six months later he signed for Altrincham before retiring in September 2015 due to a hip injury. He came out of retirement to sign for Glossop North End in September 2016. In 2017 he played for Trafford, Colwyn Bay, and Congleton Town.
Link Information: none Question: How many players did the Doncaster Rovers have when Griffith joined the team?
Solution:
Answer: none