The American collided with James Rodriguez in his side’s 2-0 defeat to the Bundesliga champions and was carried off the pitch in tears.
The 23-year-old has made only one start this season and will hope to emulate his team-mate by scoring against his old team on Saturday.
The American international celebrated his 20th birthday with the winning effort, which came on a fortunate deflection
The Porto goalkeeper made history when he started his side’s match against Schalke on Tuesday
Europe’s premier club competition returns and the online bookmaker are expecting the La Liga champions to be the most potent attack on night one
Europe’s premier club competition returns to action on Tuesday – but who will be crowned the first Santander Player of the Week?
Porto will be keen to progress from a Champions League group stage that involves German and Turkish opposition after last year’s last-16 exit