Arsenal's record signing Alexandre Lacazette has struggled to adapt to the intensity of the Premier League, according to Arsene Wenger.
The 26-year-old moved to Emirates Stadium from Lyon in July for a fee that could reportedly rise to £52 million, making him the most expensive player in the Gunners' history.
The France centre-forward has netted eight goals in 19 league starts but is yet to fully convince for the north London side, although his manager is not concerned.
"It is always a surprise for the players," Wenger said of the adjustment required from new arrivals.
"You accelerate and play more and the body needs to get used to it, the mind as well. It's a difficult period, the first year, because the family comes over and it's a bit less football-orientated.
"But you get used to it and he has played many games until now and I would say that the physical pressure on the strikers here in England has become absolutely massive."
Chelsea also broke their transfer record to bring in Alvaro Morata from Real Madrid, and the Spain international has experienced similar difficulties after a flying start.
"It's normal," Wenger said. "Morata, like Lacazette, he fights. But in England you play against teams who are organised and can play physically with 90 minutes intensity. The defenders have become much quicker than before. They are all athletes now at the back.
"What he [Lacazette] has worked on is to cope with the intensity of the challenges. In France, if you go down it's a free-kick. In England, you go down and it's no free-kick. That is much more difficult for a striker to get used to.
"This guy is used to scoring 30 goals per year so at the moment, even if he says no, I am sure he is frustrated."
|WATCH: Sabalenka wins point using racquet throat|
|Federer, Djokovic and Zverev among Australian Open first-round winners|
|Kubica gets reserve role as Williams hire Sirotkin|
|Shambolic Stars out after Sixers thrashing|
|Wales pick uncapped Worcester wing Adams in Six Nations squad|
|Tevez: CSL spell was a holiday|
|Mignolet considering Liverpool future|
|Laidlaw among several returning stars in Scotland Six Nations squad|
|´Fairy tale´ 2017 motivation for Federer|
|Fred waiting for Guardiola call amid Man City speculation|
|Dominant Federer makes light work of Bedene|
|Halep faces nervous wait over ankle injury|
|Inter confident but patient over Rafinha|
|Kohli fined after umpire outburst|
|Djokovic hits back at Australian Open boycott suggestions|
|De Grandhomme lifts Black Caps to win in Taylor´s 200th ODI|
|Giggs had counselling after Old Trafford exit|
|Durant continues dominance over Cavs as Warriors win|
|Halep survives scare and rolled ankle at Melbourne Park|
|Westbrook ejected against Kings after arguing call|
|Djokovic eases past Young on return|
|Sharapova staying grounded after Melbourne win|
|Neville: Mourinho would happily swap Mkhitaryan for Sanchez|
|Raonic suffers surprise loss in Melbourne|
|Sharapova wins on return to Australian Open|
|Pirates send McCutchen to Giants|
|Man United becoming Pogba´s team – Mourinho|
|Saints, Steelers coaching staffs to lead Pro Bowl teams|
|LeBron says we cannot let racism ´conquer us as people´|
|Super Bowl hopeful Belichick cautiously preparing for Jaguars|
|Cardinals veteran Yadier Molina: Three more years before retirement|
|The best finishes in NFL playoff history - Where does Keenum & Diggs´ Minneapolis miracle rank?|
|Can ´talking with everyone´ but hints at Liverpool stay|
|Mourinho ´not unconfident´ Manchester United will sign Sanchez|
|Pogba warns City that United will not give up the chase|
|Assist king Pogba matches De Bruyne, Sane despite injury and suspension|
|Manchester United 3 Stoke City 0: Valencia, Martial and Lukaku trim gap at the top|
|Shaw feeling on top of his game amid United run|
|Ulster and Ireland wing Bowe to retire|
|Mkhitaryan left out by Manchester United amid Arsenal talk|
|Inter secure Lopez on loan from Benfica|
|Hurst marvels at hat-trick maestro Kane|
|WATCH: Neymar nutmegging for fun in PSG training|
|Best eager to sort out Ireland future|
|Bastareaud and Haskell to learn fate on Wednesday|
|Nantes´ Carlos has red card overturned after being kicked by referee|
|De Villiers leads Proteas´ recovery following imperious Kohli century|
|´Logical´ for Aubameyang to stay at Dortmund, says Stoger|
|Di Resta out of Williams running|
|Stokes ´keen´ for court appearance after affray charge|
|Titans part ways with Mularkey|
|Stupid not to - Giggs seeks Fergie´s advice upon taking Wales job|
|Young hails Wasps´ capture of ´world class´ Sopoaga|
|England all-rounder Stokes charged with affray|
|Nadal expects to get better in Melbourne|
|Suarez feared Chiellini bite would derail Barca transfer|
|Dortmund sign reported Man United target Akanji|
|Short stars again in Hurricanes´ fifth straight win|
|Bangladesh trounce Zimbabwe in tri-nations opener|
|Wales confirm Giggs appointment|
|Barcelona´s Dembele out for up to four weeks|
|Nadal through as five seeds fall in Australian Open first round|
|Williams, Stephens out as American women stumble at Australian Open|
|Wozniacki not getting carried away as seeds tumble|
|Struggling Stoke appoint Lambert|
|Referee suspended until further notice after kicking Nantes´ Carlos|
|Mercedes lead tributes to Gurney|
|Coutinho´s ´deserved´ Barca move, says Figo|
|Toulon stand by Bastareaud after alleged homophobic slur|
|Burgos no match for sensational Nadal|