In a statement on Wednesday morning, the Irishman, who played 19 games for Essendon in 2017, said he was enjoying his time at the club and keen to keep building towards future success.

He was recruited from County Tyrone as a category B rookie in 2014. The 184-centimetre defender has so far played 33 games, initially starting out as a forward before switching to the back line.

"Essendon has made my transition into football an easy and enjoyable one," McKenna said.

"We have a great group of players, and the strong bonds I've made with my teammates have helped me develop my game and drive me to want to achieve success.

"I've enjoyed every moment with the club and am happy I will continue to represent the club for another four years.

"I believe in our vision, we have an exciting future and over the next four years I hope we can achieve the success we are working towards."

McKenna had an average of 17 disposals, four marks and two tackles per game in season 2017, when the Bombers made the finals but exited in the first week after being thumped by Sydney in their elimination final.

Bombers coach John Worsfold said McKenna was "an incredible fit for what we are building at Essendon".

"His efforts week in, week out, has made him a fundamental part of the squad," Worsfold said.

"Conor is still learning our game and with continued hard work he will improve rapidly and become an outstanding rebounding defender."

Meanwhile, the Giants' Lachie Whitfield has made the "pretty easy decision" to sign a new contract extension with GWS until the end of 2020.

Whitfield, who was banned for six months for attempting to evade a drug test and missed the first eight rounds of the 2017 season, was already signed until the end of 2018

"This has been my home since I arrived five years ago and this is where I want to play my football," the 23-year-old said in a statement on Wednesday.

"I love the Sydney lifestyle and wouldn't want to be anywhere else.

"We're building something special and I'm looking forward to what's to come in the next few years."

The new deal comes as the Giants prepare for a knockout semi-final against West Coast at Spotless Stadium on Saturday night, with the winner to face Richmond in a preliminary final.

Whitfield joins Jacob Hopper, Daniel Lloyd and Dawson Simpson in re-signing with the Giants in recent weeks.

The Giants are still awaiting a decision from the highly sought after Josh Kelly but Wayne Campbell, the Giants' general manager of football, remained positive on Wednesday that he would stay at the club.

"There's no pressure on Josh. Everyone is fairly positive Josh will be here in 2018 & 2019," said Campbell on RSN.