REIMS, France, Aug 29 (Reuters) - Lionel Messi came on as a second-half substitute to make his debut with Paris St Germain in a Ligue 1 game against Stade de Reims at the Auguste Delaune stadium on Sunday. The Argentina forward, who joined PSG from Barcelona on a two-year contract earlier this month, replaced Brazil striker Neymar in the 66th minute.