Stoke captain Ryan Shawcross believes criticism aimed at Karl Henry and Nigel de Jong is unfair as mistimed tackles are inevitable in football.[LNB] Wolves skipper Henry was shown a red card on Saturday for a sliding tackle that sent Wigan's Jordi Gomez into a cartwheel, and a challenge from City midfielder De Jong the next day left Newcastle's Hatem Ben Arfa with a broken leg.[LNB]In each case the tackler has been widely vilified, with Henry - who was also involved in the collision earlier this season which saw Fulham striker Bobby Zamora break his leg - publicly apologising for the Gomez challenge and De Jong being left out of Bert van Marwijk's Holland squad for the Euro 2012 qualifiers against Moldova and Sweden.[LNB]In February, Shawcross found himself in the spotlight having made a tackle that fractured Arsenal midfielder Aaron Ramsey's leg, and the Potters centre-back insists the speed of the game means that some challenges will inevitably be mistimed.[LNB]Asked if he felt the criticism of players like Henry and De Jong was too harsh, Shawcross said: "Yes, sometimes it is.[LNB]"As a player, the likes of Henry and De Jong I'm sure didn't go out to injure another player on purpose.[LNB]"It's part and parcel of football - they are tough-tackling central midfielders whose games are based on making tackles, winning the ball and then giving it to the ball-players. Sometimes injuries are caused.[LNB]"You have just got to accept in these times, with the ball moving so fast and the player moving so fast, sometimes you are going to mistime tackles and that is when injuries can happen."[LNB]Shawcross received a three-match suspension after being sent off for the foul on Ramsey.[LNB]His next start was against Everton and the 23-year-old points to an incident in that game as evidence of the fine margins involved in modern-day tackling.[LNB]"In the game I returned in against Everton, there was a tackle exactly the same as the Ramsey one but I was a bit quicker and got the ball, and that shows the difference," Shawcross said.[LNB]"It is just a case of half-seconds between you getting the ball or not, and sometimes if you don't get the ball, you can cause serious injury, which has been shown at the weekend.[LNB]"But it is part of football and something that we have to accept."[LNB]The Ramsey incident came on the same weekend that Shawcross received his first call-up to the England squad, although the defender did not play in the friendly against Egypt and has not returned to the international fold since.[LNB]Shawcross feels his form is improving as he looks to emulate last season's standards, and he has also backed Jermaine Pennant to earn a first England cap if the new Stoke winger can continue to produce performances like those he has so far following his move from Real Zaragoza in August.[LNB]"He has definitely got the quality," Shawcross said.[LNB]"I don't think he has played enough games at the moment to get in the England squad, but I'm sure if he gets a run of 10 or 15 games and performs like he has done in the last couple, he will be in the reckoning."