Croatia coach Zlatko Dalic felt fatigue was a key factor as England's late comeback condemned his team to Nations League relegation.
Andrej Kramaric's opener in Sunday's decisive meeting at Wembley looked set to give the World Cup finalists another victory over the Three Lions.
But Harry Kane's effort ran for Jesse Lingard to equalise before the hosts' captain converted a Ben Chilwell cross in the 85th minute to instead book England's place in the Finals.
Croatia were without key midfielder Ivan Rakitic due to injury and had to replace right-back Sime Vrsaljko, who made a brilliant tackle to deny Marcus Rashford, in the first half.
Ante Rebic was also withdrawn at the break, while England could introduce Lingard, Dele Alli and Jadon Sancho, and Dalic said his stretched squad lacked energy following their exertions in securing a last-gasp 3-2 win against Spain on Thursday.
"First of all congratulations to England on a deserved win and qualifying for the final four," Dalic told a news conference. "We didn't play well in the first half and we were a bit lucky to get in at 0-0, but the second half was better.
"We had a few chances after scoring but conceded two set pieces and in the end it's fair as they are a part of the game and a fair result. I'm not a sad man, I'm proud and we played well, I congratulated them on their performance.
"[Conditioning] was our biggest problem as you saw with Sime Vrsaljko and Ante Rebic, it was very difficult to recover from the match against Spain. We don't have a big roster of players and missing five players means we can't just replace them.
"In the second half England were not very dangerous, we played well but we lacked concentration in the last 15 minutes which can be taken from our condition physically.
"We didn't have many solutions on the bench, look at who came in for England - they had two players worth €100million and we had two Under-21s and we'd already made two substitutions so we didn't have a lot of options."
8 - Harry Kane scored eight goals for England in 2018, the most by a player in a calendar year since Wayne Rooney scored eight in 2014. Mantle. pic.twitter.com/H0d7khvlcC— OptaJoe (@OptaJoe) November 18, 2018
Despite their Nations League disappointment, Dalic's side can reflect on a 2018 that took Croatia to their first ever World Cup final.
"The players are very sad after the game, they were leading at Wembley and could feel the win," he added. "But they lost and that's football, we beat Spain in added time and this time we lost.
"Big picture, the law of averages evens out between teams. We can be proud of what we achieved, we deserved it, we're a small country yet we achieved great results and we're second in the world [rankings]. We have to be proud of that.
"Our first goal was to prepare for the European qualifiers and get ready for Euro 2020 so we brought in new players and managed to do that. We showed we have quality for the future, young players have a foundation for the future."
|Mbappe admits frank discussions inspired PSG´s Champions League progress|
|Klopp: Napoli had no answers to outstanding Liverpool|
|Pochettino proud of ´massive, massive achievement´ for Spurs|
|Barcelona equal Champions League record|
|Composed and controlled Liverpool see off Napoli to progress|
|Tenerife back to winning ways, AEK beat Hapoel|
|Howedes ´hurt´ after emotional Schalke return ends in defeat|
|Kane ´buzzing´ over ´not bad´ draw at Barcelona|
|Robertson hails Alisson´s ´unbelievable´ save as Liverpool progress|
|Red Star Belgrade 1 Paris Saint-Germain 4: Neymar brilliance helps secure Group C top spot|
|Inter 1 PSV 1: Icardi header not enough for the Nerazzurri|
|Liverpool 1 Napoli 0: Superb Salah sends Reds through|
|Club Brugge 0 Atletico Madrid 0: Simeone´s men miss out on top spot|
|Barcelona 1 Tottenham 1: Lucas rescues Spurs late on to secure progress|
|Monaco 0 Borussia Dortmund 2: Guerreiro double snatches top spot from Atletico|
|Butler´s groin strain ´nothing significant´ – 76ers coach Brown|
|Woakes, Curran among leading lights at IPL auction|
|Blue Jays release five-time All-Star Tulowitzki|
|Mourinho: Professionals care more than the fans|
|Casillas reaches 100 Champions League wins|
|Expansion franchise Cincinnati sign Garza, send Kamara to Rapids|
|Manchester City sign United States goalkeeper Steffen for reported £7m|
|Schalke 1 Lokomotiv Moscow 0: Russians miss chance for Europa League reprieve|
|Galatasaray 2 Porto 3: Terim´s men into Europa League after penalty drama|
|Jackman leaves Dragons role|
|Tottenham boosted as Barcelona bench Messi|
|Mane and Henderson in Liverpool XI to face Napoli|
|Mourinho shoots down question over how to get the best from Pogba|
|Ronaldo to start as Allegri aims to avoid Champions League big guns|
|Odriozola: I´m in love with Benzema, he´s the best number nine in the world|
|Vikings fire OC DeFilippo after loss to Seahawks|
|Marcelino suggests Valencia open to Batshuayi departure|
|Bottas to make rally debut in title-winning M-Sport Ford Fiesta|
|Kovac dismisses Pavard speculation|
|Yaya Toure leaves Olympiacos after just five appearances|
|Riise challenges Liverpool to banish Champions League disappointment against Napoli|
|We rallied around it - Durant on Green confrontation aftermath|
|Valencia ´p****d off´ with Fellaini´s controversial Young Boys winner - Soler|
|More must be done to combat racism at Premier League grounds – Chalobah|
|Napoli will not sack ´big signing´ Ancelotti if they miss Champions League qualification, says De La|
|Guardiola not interested in ´exceptional´ Saul|
|Shai gives Windies hope with thrilling ODI run chase|
|Ten Hag unsure whether to risk Ajax stars against Bayern|
|Erasmus to work with Bulls as Springboks assist Super Rugby sides|
|Paul Gascoigne pleads not guilty to sexual assault|
|Joshua is ´begging´ for unification fight, claims Wilder|
|Silva, Fernandinho add to Guardiola´s injury woes|
|Hosszu storms to 14th gold, Seto smashes Le Clos´ world record|
|Raheem is an incredible human being - Guardiola rallies behind City star Sterling|
|Sexton pens IRFU extension until 2021|
|Ajax boss Ten Hag can do big things, says Bayern chief Rummenigge|
|He´s good at basketball – Kerr running out of superlatives for Curry|
|Green thrilled to make Warriors return in victory over Timberwolves|
|Madrid squad great and humble - Solari responds to Ronaldo|
|Langer unsure what to expect from Perth wicket|
|Fournette subjected to alleged racial abuse in Titans loss - Marrone|
|Better and better - Mbappe hails Neymar link|
|It´s the end of one of the best movies you could ever see - James pays tribute to retiring Wade|
|NASA invites Curry to see moon rocks|
|No plan B for LaLiga Miami game after Barcelona withdrawal|
|Messi´s English haul, Neymar eyes hat-trick record - Champions League in Opta numbers|
|LeBron trumps Wade in last dance, Curry scores 38 points|
|Seahawks secure dominant win over Vikings|
|Iniesta visits Messi and former club Barcelona|
|Drake makes plea for ball thrown into stands after Miami miracle|
|´Toughest pretty boy I´ve ever met´ - Langer dismisses Paine concerns|
|Van Dijk says Liverpool can challenge for double ahead of Napoli decider|
|Hazard: I´ve always loved Real Madrid|
|Yankees interested in Machado, not Harper - Cashman|
|Warriors´ Curry believes moon landing was faked|