The Welsh custodian became the club's first-choice goalkeeper during the 2015/16 campaign, and capped a fine personal season by playing in a first ever FA Cup final and helping Wales reach the semi-finals of Euro 2016.
Hennessey was the Eagles’ first signing of the 2014 January transfer window after joining from League One side Wolverhampton Wanderers, having come through the ranks as a youngster at Manchester City before joining the Wolves academy set-up in 2003, signing his first professional contract two years later.
After a successful loan spell at Stockport County – where he started his professional career with a Football League record nine consecutive clean sheets – Hennessey returned to Wolves as number one for the 2007/08 season.
He helped them gain promotion to the Premier League in 2009 and played 13 top-flight games the following season, but following successive relegations into League One, he found himself loaned out to Championship side Yeovil Town at the start of the 2013/14 campaign.
However he would be snapped up by Tony Pulis and made his Eagles debut on the final day of that season in Palace's 2-2 draw with Fulham. He made seven more appearances for the side in 2014/15 before going on to establish himself as first-choice the following campaign, something he managed to achieve once again in 2016/17 as he ousted Steve Mandanda as the club's number one shot-stopper.
Hennessey has been a regular in between the sticks for the Welsh national side since making his debut in 2007 and completed a half century of caps for his country during the Red Dragons' successful Euro 2016 qualification campaign. He featured in all-but-one of their matches in the finals, where they made it to the final four before being knocked out by Portugal.