Leeds took the lead at St. James’ Park through a Raphinha curler and were dominating the game for most of the first period.
But Newcastle fought back and an Allan Saint-Maximin goal just at the brink of half-time meant the two sides went into the break level at 1-1.
The game finished with the same scoreline, but both sides had numerous other opportunities to score and Hargreaves conceded that he is not sure how the game managed to end 1-1.
He credited Newcastle for getting back into the game after conceding, but stressed that Leeds should be bitterly unhappy as the Magpies were there for the taking in the first-half.
Hargreaves said on Premier League TV after the match: “There should have been more goals in the game, it was only 1-1 and I don’t know how there weren’t more goals in the game.
“Credit Newcastle for showing a bit more spirit after they went one down, but they need more support for Saint-Maximin as he has got to do all of it alone.
“And Leeds, they will be disappointed that they didn’t win the game and didn’t put away a Newcastle side who really struggled in the first half.
“Really surprised that it finished 1-1.”
Both Leeds and Newcastle are still waiting for their first win of the season with only a point separating them in the league table.