The Japan international started the game as the Gunners thrashed the Ligue 1 side 6-0 at the Emirates.
The hosts had scored five of those goals before half-time with Tomiyasu laying on assists for Gabriel Martinelli and Martin Odegaard.
Starting at right-back, the versatile defender was a constant threat in the first period but was replaced at the break along with Oleksandr Zinchenko, with Ben White and Jakub Kiwior onto replace them.
Tomiyasu has started Arsenal’s last four matches after a spell out of the team and Arteta has reassured fans his change at half-time was not an enforced one.
‘I think he was excellent,’ Arteta said of Tomiyasu. ‘He’s played a lot of minutes and we have a really congested period.
‘We are really short at the back at the moment and we had to use the squad and make some changes, give some rest and give some minutes to all the players.’
Arsenal have qualified for the last 16 of the Champions League as group winners, giving Arteta the chance to rest some of his key players when they take on PSV Eindhoven in Netherlands in their final game on 12 December.
‘I don’t know, let’s see how we get to that game,’ Arteta said.
‘Now the job is done with what we wanted to achieve, every time we to play a football match, we want to win it and we prepare it in the best possible way.
‘But it gives us some room certainly, in relation to the squad to use some players more or less.
The Gunners now face a run of eight games in the month of December, starting at home to Wolves on Saturday afternoon.
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