Stanley I am going to have to disagree with you the Martinez substitute.
It was clear he was very worried about our left hand side. Galloway was badly exposed against Manchester City and Ivanovic would have looked to bomb forward and overpower him. It's clear Besic was selected in part due to his "legs" but also his nasty streak to try and match Ivanovic. In that context Naismith is a close like for like replacement.
We should not view Besic as just a defensive midfielder, he was chosen to limit Ivanovic and offer to support Galloway.
Galloway played an awful lot better and we also got some joy down Chelsea's right hand side, both with Besic but then with Naismith. For that reason I think Martinez was correct.
Thank you, catcher, for your thoughtful post.
Manchester City are the team in form, and likely to be this season's Champions. Chelsea were last season's Champions, but are now sadly out of form. Ivanovic has been suffering more than most. I would have preferred to see a forward - a winger, even! - put Ivanovic under pressure, both to create scoring chances and to pin him back.
The Tactical Deconstruction of the Executioners Bong agrees with you about Besic and Naismith;
"The unfortunate Besic's cameo ended in woe - as it did 12 months ago against the same opponent - this time pulling up with a hamstring injury after a collision with Zouma. Martinez opted for the only snide for snide replacement open to him, with Naismith joining the action down the left flank, and it was down this channel that a lot of the damage was done."
With three defensive midfielders, we may well have contained Chelsea. But without Naismith's golden touch, we would probably have found it much harder to achieve the victory. Let's see how respectfully Roberto approaches Swansea.