Arsenal have confirmed a double injury boost ahead of the Premier League clash against Newcastle United.
The north London giants have recently impressed in the top-flight with 10 points from the previous four games.
They have the chance to jump into the top half of the standings, should they beat the Magpies tomorrow.
Martinelli recovered from a minor ankle problem, but he was absent for the goalless draw against Crystal Palace.
Meanwhile, Tierney also missed the game with a calf issue, but he has returned to regular first-team training.
While Martinelli is deemed fit, Tierney will undergo a late fitness test to determine his involvement against the Magpies.
Elsewhere, Pablo Mari has been ruled out of the game with a mild calf problem, but he is currently going through rehabilitation.
Arsenal are presently 11th on the table with 24 points on the board.