Athanasiou, a forward, and Benning, a defenseman, each would have become a restricted free agent had they been qualified.
"At the end of the day, I think to qualify [Athanasiou] and Matt, I guess, and I talked to both of their agents a number of times over the last week with a flat [NHL salary cap], and the challenges of putting a team together with a flat cap, I made that decision," Holland said.
Athanasiou and forward Ryan Kuffner were acquired by the Oilers in a trade with the Detroit Red Wings on Feb. 24 for forward Sam Gagner, a second-round pick in the 2020 NHL Draft and in the 2021 NHL Draft.
He scored two points (one goal, one assist) in nine regular-season games after the trade; he did not score in four postseason games when Edmonton lost to the Chicago Blackhawks in the best-of-5 Stanley Cup Qualifiers.
Holland was Red Wings general manager when Athanasiou was selected in the fourth round (No. 110) of the 2012 NHL Draft. The 26-year-old has scored 156 points (84 goals, 72 assists) in 303 games in five NHL seasons.
"I'd like to have the two seconds (picks), but I guess ... my question to you would be, did you do things in your life before that you would do differently?" Holland said. "Probably. But you gather all the information at the time and you make a decision, and I'm not looking back.
"I [made the trade] because we were trying to win. I did it because he scored 30 goals (in 2018-19 for the Red Wings) and I knew him and he had talent, and I was hoping he was going to come in and give us a boost down the stretch and into the playoffs."
Benning scored eight points (one goal, seven assists) in 43 regular-season games and one assist in four postseason games. The 26-year-old signed with the Oilers as a free agent on Aug. 27, 2016, and scored 61 points (15 goals, 46 assists) in 248 games in four NHL seasons.
The NHL salary cap will remain at $81.5 million next season.
