Moberg Karlsson grabs a brace; Agnew and Laidler also on target.
Sunderland's development squad played out a 4-4 draw in a friendly north of the border at Hearts on Tuesday afternoon.
David Moberg Karlsson scored twice, while Liam Agnew and Jordan Laidler also hit the target for the youngsters, who are back in league action against Stoke City on Monday (January 13).
The visitors raced into a two-goal lead with Moberg Karlsson firing home from outside the box before Agnew converted from close range.
Angus Beith pulled a goal back from the penalty spot, but Sunderland went in 3-1 ahead at the break thanks to Moberg Karlsson's second goal of the match.
Sam Nicholson reduced the arrears once again in the early stages of the second half before Beith struck to make it 3-3.
Laidler then restored Sunderland's lead with just three minutes to go, but there was still a goal to come as Rhys Craigie salvaged a draw with the hosts with a goal in stoppage time.
Coach Kevin Ball said: "We were great in the first half but inconsistent in the second."