Watt was left needing treatment for what appeared to be a shin injury following a strong challenge just inside the Maldon half and was eventually replaced by youngster Ryan Melaugh.
It was a worrying moment for the U’s, with their season-opener at Gillingham now less than a week away.
However, assistant manager Kinsella, who was in charge of the U’s side at Park Drive, said they did not want to take any risks, with the 2013-14 League One campaign just around the corner.
Kinsella said: “We took Sanchez off as a precaution.
“It wasn’t a nasty tackle; it was a fair challenge but perhaps not in pre-season.
“It was a little bit over the top in terms of enthusiasm but it would be a fair one this weekend, when the league starts.
“A tackle like that at Gillingham on Saturday would be a great tackle but in pre-season, we want to keep our players on their feet.
“When you have players like Sanchez, the only way to stop them is by tackling them like that.
“Players like Sanchez are very clever, technical players and they can invite a tackle.”
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