The versatile defender arrived from Spanish club Cordoba last week for a reported £500,000 fee.
Crespo, 28, played 29 games for Cordoba last season, seeing time at every position across defence as the team finished bottom of La Liga.
Nevertheless, despite the club’s relegation, the Spaniard impressed enough during his time at the Estadio Nuevo Arcangel to attract the interest of Sherwood, who opted to fork out a reported £500,000 fee to bring him to the Midlands last week.
The former Sevilla product, who has also had spells at Italian clubs Padova and Bologna, might not be a first-choice starter at Villa Park but, having shown well against the likes of Cristiano Ronaldo last term, his new boss believes he will be an important contributor in the Premier League.
“We’re looking for someone there who could cover all positions across the back and Jose comes into that category,” said Sherwood. “He played everywhere across the back last season in LA Liga and played against Cristian Ronaldo at left-back. He can play right-back, either centre-back positons.
“He likes to defend. First and foremost, he wants to be a defender – and he’s not short of ability on the football either.
“He was a steal really. He was no money and someone who I feel can be vital to the squad. You need players like him who are versatile and are really able to step up at any time.”
Crespo is Villa’s third defensive signing of the summer following the previous additions of Micah Richards and left-back Jordan Amavi but, unlike his fellow recruits, the former Under-21 international looks set to begin the new campaign on the bench at best.
While he did make his debut as a starter at right-back in the weekend’s pre-season finale against Nottingham Forest, the versatile defender looked a tad off the pace before being substitute for Alan Hutton in the 34th-minute after taking a knock to his right knee.
Having walked off the pitch without aid, the problem is not thought to be serious but it could be enough to rule him out of the Premier League opener at Bournemouth, where Sherwood is expected to go with a backline of Hutton, captain Richards, Ciaran Clark and Amavi.
Nevertheless, with the defence lacking cover as it is, even before taking into account the questionable fitness records of backups Jores Okore and Nathan Baker, there should be a decent amount of opportunities for him to see minutes going forward.