Arsenal have been handed a major injury boost after Mikel Merino trained ahead of the first leg of their Champions League semi-final with Paris Saint-Germain. Ben White has also been passed fit for the game at Emirates Stadium on Tuesday. Merino and White missed last Wednesday’s 2-2 draw with Crystal Palace. Both players were left out of the squad entirely and Mikel Arteta confirmed they were not fit enough to even make the bench. “They couldn’t be involved - if not they would have been,” said Arteta. “Unfortunately, after the game [against Ipswich] we had some issues and they are not fit.” Asked after the draw with Palace if Merino and White would be fit to face PSG, Arteta said: “We’ll have to wait and see, they weren’t able to be in the squad today.” Riccardo Calafiori has been out since March after injuring his knee while on Italy duty. Arteta confirmed recently that the defender was progressing well in his recovery in the hope he could feature against PSG. Jorginho will miss the first leg against PSG with the a rib injury he suffered against Brentford this month. Arsenal will also be without Thomas Partey for their first leg against PSG. The Ghana midfielder is suspended after picking up his third yellow card in the Champions League this season in the second-leg win over Real Madrid in the quarter-finals.