Report: Arsenal Watch Porto's Hector Herrera Amid Transfer Rumours

Arsenal reportedly sent an official to watch Hector Herrera and Porto take on Galatasaray during Wednesday's UEFA Champions League action. 

According to A Bola (h/t Sport Witness), the Mexico international impressed in the 1-0 win. He's set to become a free agent and has been linked to the Gunners in recent times.

Per Sport Witness, both European and Mexican media have linked Herrera to the Gunners, and there were even incorrect claims a deal was close.

The 28-year-old has been with Porto since 2013 and is expected to take the next step in his career this coming summer. As an experienced veteran in his prime available on a free transfer, he could be one of the top value signings available.

A Bola have previously linked Arsenal rivals Tottenham Hotspur with Herrera:

The all-action midfielder has an excellent all-round skill set, doing most of his work in a central role. He's an adept defender with excellent stamina and the willingness to track back but also makes frequent appearances near the opposing goal and is an able finisher.

He could be a good replacement for one of Arsenal's own pending free agents, Aaron Ramsey. The Welshman appears to be on his way out, per BBC Sport's David Ornstein:

According to Sport Witness, A Bola also reported Crystal Palace kept an eye on Herrera in the match against Galatasaray.

Herrera seems more likely to seek a move to a Champions League club, although he would receive more guarantees of playing time with the Eagles.

New Arsenal manager Unai Emery has frequently used a double pivot so far this season. If the versatile Ramsey leaves, there would be need for another midfielder with range in the squad.