Complex sentence: Along the way Gus reconnects with Johnny (Timberlake), a scout for the Boston Red Sox who also has a friendly history with Gus as he scouted him when Johnny was a baseball player.
Split into simpler sentences: Along the way Gus reconnects with a former player he scouted called Johnny (Timberlake) who is working as a scout for the Boston Red Sox. Johnny has a friendly history with Gus as he scouted him when Johnny was a baseball player.