The most prolific performer to enter the NCAA transfer portal this offseason has found a destination.

Former Pittsburgh wide receiver Jordan Addison will transfer to USC to play this fall, he announced on social media Thursday.

pic.twitter.com/5oN0ZVGsCC

— Jordan Addison (@Espn_Jordan) May 19, 2022

Addison visited USC officially over the past weekend and will reunite with star sophomore quarterback Caleb Williams, as both hail from the Washington, D.C., area. Addison's decision to go to USC gives coach Lincoln Riley the two most important transfer additions of the offseason, as Addison and Williams were arguably the most coveted players to enter the portal.

In his statement posted to social media, Addison described the decision as "very difficult" and said he would always be grateful to the University of Pittsburgh.

"Winning an ACC championship is ours forever. Those true friendships will last. A part of me will always be H2P," he wrote.

"I have now carefully considered the advice of my family and close friends and fully weighed both the risks and benefits associated with my decision. I also respect that others may make a different choice. But for me, I will continue my full development as a student athlete by enrolling at USC."

Addison earned first-team All-American honors at Pittsburgh last season and won the Biletnikoff Award for the country's most outstanding receiver. He entered the NCAA transfer portal May 3 and took visits to USC and Texas. He considered staying at Pitt and also contemplated Alabama and Oregon but didn't end up visiting either school.

Addison's move out west is a blow to Pittsburgh, as the defending ACC champion lost its best returning player after going 11-3 last season. USC went 4-8 and has rebuilt its roster so significantly in Riley's first year that a majority of the starters next season are expected to come from the NCAA transfer portal.

Pitt coach Pat Narduzzi had multiple contentious phone calls with Riley soon after Addison broached entering the portal, sources told ESPN earlier in the month. No known evidence of tampering has emerged, however.

The transfer of Addison has been viewed as a beacon of an offseason filled with change. The notion of an established underclassman jumping programs wasn't something that happened in college football until recently. Thanks to a flurry of rule changes -- most notably one-time transfer rules -- fluid player movement has become part of the sport's landscape.

Although Williams' transfer was viewed as a collision of one-time transfer and name, image and likeness rules, it was viewed through a different prism because his college coach at Oklahoma, Riley, left for USC and Williams followed him. Addison's transfer to USC reinforced the reality that all rosters are fluid and the sport's biggest stars can jump from program to program with relative ease.

Sources made clear to ESPN throughout the process that Addison's professional future was going to lead his decision-making.

The addition of Addison gives USC one of the country's best wide receiver duos, as he'll join Oklahoma transfer Mario Williams there. Addison caught 100 passes for 1,593 yards and 17 touchdowns last season. He projects as a first-round NFL draft pick in 2023 but, at 6 feet tall and 175 pounds, is unlikely to crack the top 10.

Mario Williams, who earned ESPN True Freshman All-American honors last year, caught 35 balls for 380 yards and four touchdowns. Brenden Rice, the son of NFL legend Jerry Rice, also transferred in, from Colorado, where he averaged 14.2 yards per catch last season.

Addison's transfer further reinforces the optimism behind Riley's hire at USC, as the lure of the prolific offenses he built and called at Oklahoma have moved to Los Angeles. Although USC's offensive line has questions and the defense was one of the worst in the conference last season, there are key players who have transferred in to rejuvenate the Trojans on the offensive side of the ball.