The Deans suffered a 3-1 defeat to two divisions higher Isthmian League Premier Division Bognor at Five Heads Park on Saturday.
It followed tricky friendlies with National League South Hawks, Gosport Borough, Hartley Wintney and Chichester City.
Horndean now cap their pre-season with Hampshire Premier League Clanfield the visitors to Five Heads Park tomorrow.
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And with Horndean kicking the new Wessex League Premier Division season off against Alresford a week tomorrow, Birmingham says his squad have been provided the best chance to make sure they're up to speed and ready to make a blistering start.
The Deans boss said: 'I think the lads have been outstanding, they’ve been absolutely brilliant, it’s been a tough pre-season with everything that’s gone on the past 15-18 months.
‘I can imagine all clubs are like it.
‘I remember when we first went back to pre-season and we were thinking, ‘this is going to take forever,’ but as soon as the games started coming it’s been very quick.
‘We’ve had Hawks, Chichester City, Hartley Wintney and Bognor, so we’ve had a tough pre-season.
‘It’s great for us, they all know we try to do things the right way, they’ve all complimented us on the style we play and also how nice, friendly and warm the club is as well so that’s great and it makes our job of getting them again a lot easier.'
Forward Harry Jackson netted Horndean's late consolation in the 3-1 defeat to Bognor.
Ex-Baffins and Portchester striker Jason Parish (2) and Nathan Odokonyero had earlier put the game beyond the Deans.
Birmingham felt his side were still feeling the effects on the effort they put in to beat Gosport Borough 4-3 the previous Tuesday.
But the Deans boss was very complimentary of Jack Pearce's Bognor side.
Birmingham said: 'We put a lot of effort in against Gosport and I thought we looked a little bit leggy at times (against Bognor), but you’re playing against a very, very good side who bop it about for fun.
'We gifted the three goals, they were gifted, they didn’t have to work hard.
‘You look at it, we were getting back into the game, we moved the ball around but without really trying to penetrate or hurt them.
'We got extra minutes in, it was a great fitness test and it’s great for Horndean to host a club like Bognor.'