The problems at the club are by no means exclusively down to Moyes, and many predate his arrival last summer.
Fabio Borini forced Artur Boruc into an 11th-minute save with a rising drive, but it was Defoe to whom most of the better openings fell.
You have to give Sunderland credit, they don't hang about.
An 11-game wait for their first victory of the season set the tone, with Bournemouth ironically the first team they beat, a 2-1 win at the Vitality Stadium in November thanks to a Defoe penalty.
The Black Cats headed into the Stadium of Light clash against the Cherries needing a result, but Josh King's 88th-minute victor means the north east club will be playing football in the Championship next season.
Basement-side Sunderland, who have been battling the drop for the last four seasons, are 12 points adrift of the safety zone with five games to play as they prepare to host 13th-placed Bournemouth on Saturday.
GETTY Anthony Joshua and Wladimir Klitschko go head-to-head at Wembley on Saturday
The Sunderland boss has faced fan ire in recent weeks, but insisted after the 1-0 defeat to Middlesbrough that he will not walk away from the club.
"I want Jamie Vardy to finish on a high", said Leicester manager Craig Shakespeare, whose side sit 11th.
King's goal pushed Sunderland over the edge and with the club's fans angry at the poor leadership of Moyes and Short, there is no guarantee they will bounce back.
With Moyes suggesting he may consider his future at the end of the season, some Sunderland fans may feel a show of displeasure will convince him to walk away from a job which has become increasingly hard with each passing fixture of the campaign. "As players, we have to stand up and be counted and do that". "We have got to find that and we have got to get it back quickly". While there's hope for Sunderland, they'll keep going. We need to win tomorrow.
"Look at the size of the clubs we are competing against week in, week out", Bournemouth manager Eddie Howe said. "There is significant work to be done over the summer and when the season is concluded, we intend to share our plans to move forward with our supporters", he added. "We'll do everything we can to get it right". "We're all disappointed and I feel more for the supporters".
"It is about continuing our progression and momentum, but it will be a hard game, any away game in the Premier League is tough, so we will not be underestimating Sunderland".