All it took for Arians to come to the conclusion was to watch Barkley at Penn State in 2017.
"I saw a few games on television and he piqued my interest," Arians told Matt Lombardo of NJ Advance Media. "When you're watching him, you think he's like 190 pounds. Then, you see that he's 235 pounds and it's like; holy s--t, he's special."
"Whether it's kickoff returns, receiving yards, the play the other day in practice when he pulled his hamstring running on a deep-ball as a wide receiver. He brings so much."
Arians' review on the second-overall pick of the 2018 NFL Draft carries weight when considering the former coach's time around some of the league's elite versatile running backs.
From 1998 to 2000, Arians served on the Indianapolis Colts coaching staff and was around Marshall Faulk and Edgerrin James.
During his recent stint as head coach of the Arizona Cardinals, Arians had running David Johnson, whom Arians once labeled as a Transformer because of Johnson's ability to do it all out of the backfield.
So, it doesn't surprise that Arians sees a lot of similarities in Barkley's skill set as a runner and receiver out of the backfield to Johnson.
"He reminds me a lot of David Johnson, who I had," Arians said. "Man, that's special stuff, because, he's truly a mismatch. If teams want to go double-team Odell [Beckham Jr.], then Saquon's going to kill it inside."
The 6-foot, 233-pound Barkley joined the Giants following an accomplished career at Penn State, where he totaled 3,843 yards rushing, 1,195 yards receiving and 51 total touchdowns.
If the versatile Barkley lives up to Arians' praise, the Giants' offense will thrive and the team's two-year run of ranking near the bottom of the league in rushing will end.